If you have a Central Pneumatic air compressor, and you didn’t buy it used, from a garage sale, or from on on-line end-of-line wholesaler, odds are pretty good that you bought it at Harbor Freight.
In 2017, Harbor Freight offers about 35 different Central Pneumatic air compressors, from a 1/6 HP air brush style to a 5 HP, almost commercial type, on a 60 gallon air tank. They even have one model of a gas-powered, wheelbarrow style, that is quite well priced.
Central Pneumatic air compressors can be purchased through Harbor Freight on-line, or at the many Harbor Freight stores found throughout the United States.
Buyers of Central Pneumatic air compressors are, pretty much I think, aware that you get what you pay for. This line of compressors is entry level. I don’t believe they are made for serious compressed air use, where whether or not a compressor works means that trades persons do or don’t do work that day.
Which is not to say, if you are a periodic user of compressed air – the typical small workshop or home garage for example – you won’t be happy with this brand of compressors reliability. I just wouldn’t put the supply of my plants air system at the mercy of this particular brand.
While Harbor Freight boasts of having manufacturing around the world, I would be surprised if they actually owned a factory that makes air compressors. Their entire line is similar or identical to compressors of other brands with different colors and different labels. I could be wrong and will be happy to indicate so if someone can provide proof that HF actually makes their own compressors.
Regardless of whether they make them or not, try to find parts for a Central Pneumatic air compressor. Aside from pressure switches, gauges, regulators, PRV’s and check valves (all the same as those found on many other brands) there are very few repair parts for the compressor pump or the motor. Parts from other Central Pneumatic air compressors can often be used on other models of this brand. If you can scrounge or buy a non-working compressor, some parts from the old can be reused to fix others that have failed. Depends on your skill level as to whether or not this works for you.
If you are having a problem with your Central Pneumatic air compressor why not add a question or comment here? Include the model number of your compressor. As a result, perhaps the Central Pneumatic air compressor owner/user family, which is a huge one, can offer advice as some of them will, undoubtedly, already dealt with the same problem you are experiencing with your HF Central Pneumatic air compressor.
I just bought a 21 gal 125psi upright central Pneumatic compressor at a Harbor Freight parking lot sale. It runs fine but wouldn’t build pressure over 40 psi. I checked the reed valves and one was broken. I order a new set and in the process of fixing it I broke the exhaust tube. Any idea where one could be bought from? Would it be worth it to try to fix it or just carry… Read more »
Don’t know what you mean by the exhaust tube Sonny. However, based on your experience so far, if this were mine, it would go right back to the store and exchange or get a refund.
Hello i have a 2.5 hp 10 gal 125 psi central Pneumatic compressor , when i run it it runs for a minute then kicks off , even with valve open , i bypassed the reset and it ran fine and filked up to 125 psi , i then shut it off worried it woukd blow up lol Could i just need a new reset button ? Thanks Geneo
While it is possible the reset is the problem, the more likelihood is that the motor is overheating. What causes this? A too great load from the pump to the motor, like the pump is mechanically damaged and can’t cycle properly. Or, a pump head valve has failed, preventing proper air flow, and the motor is now running too long as a result and overheats, or, the motor start / run capacitor is failing and… Read more »
I have 2.5 hp 21gal stand up pressure switch needs replacement, where to get one?
Go to this page and scroll down to the pages about the pressure switch. You’ll find your answer there, I suspect. If not, add a photo of the failed pressure switch as a comment to this thread, please.
thank you for offering a place to post. I am finding that the valve that controls releasing pressure from the tank to the tool is not opening. Nothing changes, tho, unpredicably it worked for about 10 mins today…Any suggested fixes for that?
Not knowing the model of Central Pneumatic air compressor you have makes recommending a replacement impossible. If your question is about what I would call the pressure regulator, and if turning the knob does not change the pressure setting on the regulator gauge, and if the tank pressure is higher than the regulator setting, and pushing or pulling on the knob of the regulator does not reengage it, then it would be time to replace… Read more »
So I usually have to empty all the air out of the compressor before it will start and if it’s cold it is even worse I have the 2.5 21 gallon upright I was wondering if this ‘t’ fix would help if so pictures would be nice 😉
Scott, please visit this page and scroll down to the section about compressors that won’t start.
Emptying the air before starting suggests an unloader issue.
When you say ” I was wondering if this ‘t’ fix would help if so pictures would be nice” I’m sorry, I have no idea what you are talking about. Please clarify.
sorry I thought I was replying to the post about how the guy put a t in and two of the pressure valves because his wouldnt get going
I have a central pneumatic air compressor model# 67847 2.5hp 21GAL 125maximum psi and it keeps shutting off right at start off I plug it in hit the on button runs for like 3sec and shuts off
Luis, now old, well used, using an extension cord?
I have the same one as Noel and every time we turn it on it’ll be on for a few seconds then the reset button pops out and it turns off.
That’s typically an overheating issue, and the overheating can be caused by a number of things, including power supply. Please look at the troubleshooting page, scroll down to the pages that address this issue, and then add a comment here with more questions if you still have them. Thanks.
I have a 21gal stand up or the central pneumatic and all of a sudden it stopped building pressure. I used it Thursday just fine started today and it wont build pressure. Help
Noel, are you saying that it stops running, or that it’s running and not building pressure, please?
Sorry i should have bee more clear. It will run but wont build any pressure past 30. Once it gets to 30 it will continue to run but no more pressure will build. the picture is where the gauge will stop but the compressor will continue to run.
That helps, Noel. That compressor symptom suggests a couple of things. If the gasket in the pump is failing, it may leak badly at 30 PSI and the air doesn’t get driven into the tank, but instead goes back and forth inside the pump. Or, it could be a broken valve.
Have a look at this page, and scroll down to the pages that address this issue for more specific help. Okay?
Thank you. I will look into this and hopefully it’s a quick fix
Would this be the problem or should I dig deeper. I think it’s called a reed.
THis was the problem. Compressor back up and running. Thank you for your help Willyr
Glad to have been of help. Have a good one.
I’ve seen a lot of comments on the 21 gal Central Pneumatics air compressor with starting issues. I tried all the suggestions to get mine to start consistently – new cold start valve, new capacitor, checked the bypass valve. I cured mine by putting a tee in place of my cold start valve and then put 2 cold start valves into the tee. They still close at 2.5lbs of pressure but it takes a second… Read more »
Excellent tip, Paul. Thank you.
I have a 10gal 2.5hp central pneumatic air compressor the oil fill cap blew off where can I get another one
I just Googled “central pneumatic compressor oil fill tube cap” and found a bunch. Have a look if you haven’t already done so.
I have a Central Pneumatic air compressor #69669. Where can I get the three eared inlet valve reed?
Angie, please upload a photo of the inlet valve reed you are seeking. There are non-OEM reed valves available, but I don’t know which is yours.
Just wanted to give everyone an update on what ive recently done to my troublesome 21gal 2.5hp compressor. So after the 3rd reed broke on me I decided to trace the good reed i had left onto a piece of .012 feeler gauge. I shaped it to match almost exactly and put it back together. Only this time i drained the HF compressor oil and filled with Mobile 1 full synthetic 5w 20. Also loosened… Read more »
I have a 69669 air compressor. I nedd a compositor for it where can I get one?
My central pneumatic compressor will run and build air but compressor won’t kick off. What is the problem?
Dan, if you are saying that your compressor tank pressure blows by the normal cut out, and then the PRV lets go to vent over-pressure, that’s typically an issue with the pressure switch failing and not responding to the tank pressure.
My compressor will build air but not kick off it keeps running.
Model number? What pressure does it build to, or, is it building pressure past the normal stopping point and blowing the PRV open, please Dan?
I have a model #47065 21 gal and the compressor wouldn’t build pressure. I took off pressure switch and took it apart and noticed that the rubber diaphragm has holes in it. Where do I find a replacement diaphragm.
I very much suspect that you won’t find a diaphragm unless you craft your own. I expect you’ll have to buy a new switch, and since the switch of the 47065 is the same one as used on many other makes and models of compressors, visit your compressor store, look at the new compressors, find one with the same switch, and see if they have that switch in stock.
I thought so. I found one on Amazon that is the same. Should be here on Saturday. Thanks.
can’t get the Red Knob on the pressure regulator to screw down to adjust out going air
pressure. anyone with suggestions?
If lifting or pushing down on the regulator knob does not allow turning the knob to adjust the pressure, I suspect a failed regulator and a replacement is in order.
That black “reset” button just sits flush in the housing it’s in. Doesn’t really push in at all. Zero pressure on guage, compressor never shuts off, just keeps goin. How can I address this?
The reset button likely won’t do anything unless the compressor motor has gone off on thermal cut out, if it’s the button I think it is. The compressor never shuts off, and the gauge reads zero, if that’s the tank pressure gauge and not the regulator gauge, then the pump isn’t getting any air into the tank, or, you’ve got a major leak that’s bleeding air as fast as the pump can make it. Please… Read more »
I think Harbor Freight should exchange Model 62803 21gallon compressor for customers who got stuck with LEMON COMPRESSORS. Im sure they are engineered to last just outside the return policy window but if it gets even light use it will become apparent that it only looks like a functional compressor. I will not buy another big item from Harbor Freight until they show some interest in customer satisfaction.
True. It appears to have way too many failure characteristics.
I have a Central Pneumatic 21 Gallon 2.5 hp 125 PSI Compressor. Air pressure would not build over 20 PSI. Replaced reed valves and it came up to 120 PSI and cut off as normal. As I released air with blow gun as pressure dropped , the compressor wouldn’t kick back on. Completely drained tank and again tried on off switch and it would not come back on.
Are you getting power to the pressure switch? With the tank empty, is power getting to the motor. Those are the first checks, please do so and let us know.
Definitely have power to pressure switch. With empty tank, pressure comes up to 120 PSI and shuts off automatically. But when I release air down to approximately 70 PSI, motor tries to kick back in, but compressor stutters and trips reset button. Cleaned, checked, and slightly stretched cold start valve spring to hopefully allow easier start , but again with empty tank, started up fine with 120 PSI, released pressure, and got same results. Where… Read more »
See the page on this site about checking the motor capacitor. If power is getting through the switch to the motor when the pressure drops, and the motor is struggling to start, it’s typically either the cold start / unloader valve or the capacitor. Unless, the motor itself has failed. Check the capacitor and let us know if you would.
I have the 2.5 horse with a 21 gallon tank, 125 psi. When go to turn on it runs for about 5 seconds then kicks the reset button on motor out. Started out intermittently now does it everytime no matter how much air pressure is built up. It was bought brand new 2 years ago. Any help is appreciated thanks
That typically signifies a power supply issue. Not using extension cord? If not, and the compressor is plugged into the same outlet where it worked fine before, then the next step is to check the motor capacitor. The how to do that is found in the troubleshooting pages on this site.
Thank you for the info. Yes plugged into same outlet as usual and no extension cord
the thread where the unloader tube connects to the check valve ( on the check valve) is stripped- any way to fix? or where can I get a replacement check valve?. This is the 2hp 8 gal model. Thanks
Hi Richard. Dump all the compressor tank air, power down of course, and then remove the tank check valve. Google “replacement compressor tank check valve” and you’ll find many. Pick the one that matches yours.
I was going to do that, but after seeing all the trouble people had matching the threads I just slathered the whole fitting with JB Weld.. Not very elegant I know.
As long as the repair holds, and the compressor works, who cares if it’s not elegant? Sometimes building a new manifold for a compressor is the only way around it when an OEM manifold cannot be found, and the end result will be ugly, but it will work. Good on you for making the repair, one way or another!
I am looking for a Central Pneumatic 62803 21 gal. 2.5HP 125 PSI Air Compressor uploader tube. Harbor Freight customer service states they do not carry the part.
Tom, do you mean “unloader tube”? If so, remove the existing tube and either replace it with high heat urethane tubing or take the original to a good plumbing shop and they can find the parts to make your own.
What should my tank pressure gauge read on my 17 gal, 150 psi CP air compressor model 68066 when fully charged? Don’t need a 10 paragraph response!
150 PSI.
Thx will. why do you suppose it only shows 24 psi. my regulator pressure guage shows 145 when fully charge & shuts off. but tank guage only shows 24.. maybe the reason for such poor performance. Suggestions to remedy?
Turn off the compressor and dump all the air from the tank. Remove and switch the gauges. Power up the compressor again. What happens to the pressure readings?
Interesting. will do & see where ur going! don’t thimk its the gauge though. THX!
will get back to ya.
Wanna make sure I understand. By goggles U mean the sealed gauge lenses? can’t switch gauges they’re different threads.
So sorry. Typo. I meant “Remove and switch the gauges”, and yes, to determine of the one that is showing low pressure in the tank is actually working. If gauge is working, and the tank pressure only gets to 17 PSI and the compressor keeps running and can build pressure no higher – to the 150 PSI cut out pressure – then it’s likely a pump issue, maybe gasket, maybe valves, maybe the piston… need… Read more »
my 2.5 21 gal. 125psi will not start up if air is in tank..it drags then pops breaker. Help!
Please see the troubleshooting pages on this site (link from top left navigation bar) for a link to information about why this happens and what you can do about it. If after reviewing that and doing the checks if you still need help, please add a comment here.
The drain valve is seized up on a Model 67847
Can you not just replace the whole thing? Lot’s for sale on line.
Yeah. That’s probably the plan based the answers for others I found here.
I need an output regulator for my Central Pneumatic oil-less air compressor MN: 99780;: Max pressure; 155psi; air pressure out; 125 psi;air flow; 6scfm at 40psi; 4scfm at 90 psi; tank capacity;17 gal. motor; 4hp at 13,rpm.
Thanks
Hello Bill. The regulator on the 99780 is nothing more complex than a general purpose regulator you can acquire on line or at almost any good hardware or big box store that sells air compressors and equipment. Read the specs on the regulator you acquire with the same thread size (most are common) and you’ll see that almost any new one for $15 or so will do the job.
I have a Central Pneumatic Air Compressor MN:99780. It compresses the air to about 145psi the drops to 125psi as it should. The problem is that no air discharges from the tank which is full. I found no clogged lines and believe I need a new Out-put regulator. Harbor freight does not have spare parts for this compressor. What can I do?
Looking for an image of a Central Pneumatic air compressor MN:99780 unfortunately did not return any pics of this compressor, so I have no idea what the regulator looks like. However, this page may provide some guidance: https://fix-my-compressor.com/regulator-is-leaking/
If it does not, please add a photo of your current compressor regulator as a comment to this post.
Have a Central Pneumatic 2 HP 8 gal 125 psi model 67501 air compressor. motor just hums and trips reset button when there is pressure in the tank. Release pressure down to 20# , hit reset and it will pump up to normal pressure. Any ideas on the problem. It doesn’t have a start capacitor so that is out. Does the run capacitor have a dual purpose? Thanks for your help.
Some caps have dual purposes. Off hand though I’d guess that whatever unloading mechanism your Central Pneumatic 2 HP has, that isn’t working. By removing the air that essentially dumps air over the piston, emulating an unloader function, and allowing an easier restart.
If not using any extension cord or power bar at all, and with the compressor plugged right into a socket, if the problem persists, check, fix or replace the unloader next.
This is the diagram of the compressor. Sorry but I have no idea how to check out the unloader. The only reference to an unloader is #55 which is an unloader tube. Do I have to replace the pressure switch?
When the compressor reaches normal cut out pressure and the pressure switch toggles to off to stop the motor the unloader valves job is to open, and to drain any air trapped over the piston(s), helping the restart process when the compressor restarts. The unloader tube connects to the unloader valve. Empty the compressor, close the drain and start it, and allow it to run up to cut out. When it stops, a burst of… Read more »
There is an easy way to solve this problem. The motor is not turning over fast enough to build a magnetic field (Lack of power). No magnetic field equals a huge amp draw a lot of heat from the excess amperage and no useful work. In order to make things easier for the motor to turn over and build the necessary magnetic field we need to relieve the compression in the cylinder head. A ball… Read more »
Compressor oil not showing on gauge. Runs fine.
Assuming it’s oil lubed, and we don’t know that since we don’t know what model Central Pneumatic air compressor you have, there must be an oil measure. When you say oil not showing on gauge, what gauge are you referring to? Also, if it is oil lubed, and there is oil in the sump, then it will run, but possibly overheat a bit depending on how long it’s used in one go.
I have that same problem with a 2HP 21-Gal 125# vertical Central Pneumatic compressor. Oil level does not show in the sight gauge. Filling (with high quality compressor oil to replace shipping oil that self-drained during the shipping process) very slowly and carefully watching the sight gauge, I could never see anything in the sight gauge. I was concerned that it was over-filling, because it took nearly 30 OZ of new oil, and I was… Read more »
You can remove oil by taking out the screw directly underneath the sight glass. On some models it takes a phillips screwdriver, on others it’s a #5 allen wrench. The sight glass is also threaded and can be removed, which could presumably also give you an opportunity to diagnose the issue further.
Thanks for that, Darren.
Darren — Thanks for that info. Very helpful!
my 2hp 8 gallon compressor only pumps to 40lb psi with reguator wide open
Dwayne, the regulator has nothing to do with the pressure the tank gets to. The regulator only lowers the downstream pressure to the air tool. It’s the pressure switch that controls the on/off of the compressor, and if the motor is running and the pressure only gets to 40 PSI, then the pressure switch is working. The issue may be the pump itself, and if you visit the page about troubleshooting air compressors on this… Read more »
WE HAVE A CENTRAL PNEUMATIC 9 GALLON 212CC 135 psi Wheelbarrow Air Compressor 69783 and the pull cord pulley has messed up. Can I get a replacement part for it? Thanks in advance for your help.
Compressor will start up but stops whe n it reaches about 20 #
Model number? Does power stop at the switch when the compressor stops at 20 PSI, or is power still flowing past the pressure switch, Wayne?
I have a CP 21 gal compressor – model 61454 with a pressure issue. It will build up ok but when it falls back to 95 psi to restart the motor attempts to start but trips the internal circuit breaker. It appears to be pressure build up on the piston head as I can release down to 20-30 psi and it will work. Thanks in advance for any help.
Check that the unloader valve is working and please advise.
Be good to read the thread on this page as there’s info here that might help you.
I have a central pneumatic air compressor. The relief line or Unloader tube as called got broke. I need to know what size this line is I tried to convert it to copper but 1/4 is too big 3/16 is too small.
If I know the pressure switch compression fitting then I can get the right tube. Do you know the size of this fitting? Thank you.
Always good to know what model of Central Pneumatic compressor you have, Howard. All of them may not have the same size fittings. Having said that, I suspect that the non-user type fittings on your compressor are metric in size, as opposed to NPT, even though the parts you would plug an air line into are NPT, but I cannot be sure. When you say the 1/4 is too big, does that mean it slips… Read more »
tHANK YOU FOR THE FEED BACK MY MODEL IS 47065 hf SAYS THIS MODEL IS OBSO;LETE IN THE mANUAL ON pAGE 9 SHOW S PART 19a pOLYURATHANE UNLOADER TUBE BUT NO SIZE CAN BE GIVEN BY THEM OR hf HELP . HOPEFULLY YOU CAN HELP ME FIND THE CORRECT SIZE TUBE AND COMPRESSION FITTINGS THE TUBE GOES FROM THE TANK TO THE PRESSURE SWITCH BOTTOM?? THANK YOU
Hi Howard… you didn’t answer the question about the 1/4″ fitting. Would it just not thread on a similar sized thread, or, was it flopping over the threads. Usually these things are 1/4 and could be metric, like I said. If you visit a supplier of industrial air cylinders and air valves, odds are pretty good they’ve got metric tube and fittings as well as NPT tube and fittings, and can likely set you up… Read more »
Hi I have a Central Pneumatic 90385. It will not turn on. Checked outlet, valves- no luck. Never mind, I found the hidden reset button. (Nate, I left your comment because it shows others that an open reset can be an issue that prevents starting for many types of air compressors, including the Central Pneumatic variety. Any chance you might upload a photo of where you found the reset on the Central Pneumatic 90385 to… Read more »
I have a Central Pneumatic 25 hp with 21-gallon tank. When I turn the off/on switch to on the engine tries to start but shuts off and I have to press the reset button to try it again., It just won’t run. I changed the pressure switch and the same thing happened. The model number is 67947, current 14 A, Stage 1. Any help you can provide will be helpful… Thank You for your time!
Is the plug socket on a 20 amp breaker, or a 15 amp breaker? Also, try to restart it after you have dumped all the air in the tank. Did that make any difference?
Same issue on mine. In my case i added a breaker and added an outlet with no other outlets pulling from a 20 amp breaker and still no luck.
Jaimi, if you empty the compressor tank completely and then try to start it, will it start and build pressure to cut out?
If completely drained I might get 30 seconds instead of 10 before cut out.
Next thing to check is the cap. Please see this page: https://fix-my-compressor.com/air-compressor-problems-and-fixes/ and scroll down to the Capacitor section and have a look at both pages in the section if you would. Please let us know what you found.
Have a six gal. Central pneumatic compressor.. won’t start up.. check all the standard stuff cord, plug, circuit, etc.. the pump turns over nicely, belt turns, checked all connections.. can’t find a reset button….
Dave, if there is no fuse or reset in the motor circuit, and power is getting past the pressure switch to the motor, then it’s quite possibly the motor capacitor that’s the issue. There’s a page on how to test that on this site.
I have a Central Pneumatic pancake style oilless 3 gallon compressor, item #61615. The problem I am having is the pressure regulator knob (the bright red plastic one) came off of its fitting and cannot be screwed back in. Maybe the threads got stripped? Anyway, it looks like the regulator/ knob assembly can be replaced as a unit; the question is, with what? Is there a standard air tool part that can be purchased that… Read more »
I’ve added a photo of the compressor, Andy. Thing is, you may be able to find a replacement for the whole manifold. Take the cover off, Google replacement air compressor manifolds, and see if you can find one that is similar enough to fit. They all pretty much do the same thing. Failing that, and learning that a whole new compressor of this model is $59 on line, might be best to buy another and… Read more »
Does not build up air pressure, valve at top of cylinder leaks air. Does not close to allow build up of air in tank. Intake is fine.
Paul, there are many models of Central Pneumatic / Harbor Freight air compressors, and all are not the same. Since you haven’t identified which model is yours, it’s pretty hard to give specific advice, though it sounds like the cold start valve is sticking open. How about adding a comment with a couple of photos of the problem area on the pump and if you can add a photo of the information plate for the… Read more »
The model number is 61454, central pneumatic 2.5 hp, 21 gal.
I pulled off the cylinder head and also found a broken reed. I made one and replaced it, tested it and same problem. I pulled the spring out of the cold start valve, testing will see results maybe.
Any luck? I have the same issue. Metal gasket was broke and leaks from the top right at the pressure regulator. I do not want to waste money buying a new one if that isnt it
I need a belt for the 6 gal model, anyone have a part number or know where I can get one. NO, harbor fright nor central pnuemonia have them.
I took a washing machine belt to O Riley auto parts and the measured up a belt for it and it worked great. Perhaps you could try them for your compressor.
I’ll look into it, this belt has the grooves in it, 4, and is thin. I doubt they will but it’s worth a shot. Thanks for the suggestion Dan.
I have a CP #42321 Twin Tank – 2 HP, 5 Gal capacity. I have had it for ~ 10 Years. Now it will only fill the tank to 40 lbs and will not shut off (because it has not reached the shutoff pressure). I took it apart. Very simple. I expected something more complex. It uses two flat spring steel flappers for intake and out. There does not seem to be any pressure going… Read more »
If the compressor motor is running correctly, there are no leaks accounting for air loss including a leaking tank drain valve, the intake filter if any is not impeding incoming air flow, the compressor pump is cycling properly and you still have no air buildup it has to be a problem with the pump. That means bad piston seals, cylinder scratches, valves not opening fully or closing properly, or any gaskets in the pump head… Read more »
I have the 3 gallon pancake compressor. I’ve only needed it at full pressure for tire inflation or blasting air to clean tools. Now I’d like to use an 18 gauge staple gun to staple plastic onto wood. The problem is that the pressure adjustment doesn’t seem to work. I think that about 50 psi would be good for my needs. Once fully inflated, I’m seeing 80 psi. I close down the knob, shooting test… Read more »
Sounds very much like your regulator is failing. Turning the knob should result in almost instant change on the pressure reading on the regulator gauge, as long as the tank pressure is above that setting. Firing a staple should result in a tiny blip in the regulator output for a fraction of a second or two, and then regulated pressure should be back. If it’s taking a long time to build the pressure in the… Read more »
need the pump pulley for 5hp CENTRAL PNEUMATIC twin cylinder air compressor, but can’t find where to order pump pulley in the parts book that came with it. it is item 58. was moving mine and the air compressor fell over and busted the pulley.
Measure the diameter, the shaft size, note the size of the pulley “V” where the belt fits, and then Google buy pulley or sheave. You’ll find many sources. What you likely won’t find is a Harbor Freight / Central Pneumatic supplier. The pulleys will be made to some standard and odds are good that there is a supplier that has a similar pulley.
I bought the 21 gallon central pneumatic from Harbor and it worked well for small jobs for about three years now hen it started turning off after a few seconds. The fuse seems to blow after that and I cannot find a way to replace the fuse.
I have a three gallon pancake compressor that no longer loads up when turned on.
Any ideas on the issue?
Donald, won’t load up means… runs but doesn’t build pressure? If so, lots of answers as to why right here: https://fix-my-compressor.com/air-compressor-problems-and-fixes/
I have one also, and when I pulled it apart, I found the piston ring had scored up the cylinder wall badly, and so it would not compress the air in the cylinder. I have not been able to find replacement parts for it.
I bought a 2.5 HP 10 gallon cup compressor from harbor freight. I used a few times. Each time it would hum for a few seconds and throw the breakers on my GF outlets so I Had to use a non GFI outlet. Now I turn it on and I get nothing.
Not quite sure what you mean by “cup compressor” Mark. A 2.5 HP needs a fairly robust breaker, and no power bar or no extension cord use unless it’s a large diameter cord. What can you tell us about where the compressor is being used, how it’s being powered, and what else might be on the same circuit as the outlet for the compressor?
CP 26 gal. model 62629. Piston broke in two pieces. Been trying to find a replacement. Haven’t heard back from Harbor Freight yet. Any interchangeable pistons from other brands? Only had this thing 2-3 years.
Odd that a piston broke. That’s unusual Ben. What’s not unusual is the absence of parts from Harbor Freight for the compressors they sell. They expect (want?) you to throw them away and buy a new one, putting out what are essentially disposable air compressors as they appear to do. Choices? Measure up the broken piston carefully and Google “purchase replacement piston for air compressor” which will return a number of sources and sizes. You… Read more »
Just bought a new airbrush compressor for air brushing it has a water trap on it I’m still getting water into my paint anyone have suggestions
What model Central Pneumatic air compressor did you buy for your air brushing, Chad? If you are still getting water out the air brush even with a water trap on the compressor, that means that the air from the tank still has water vapor in it, and that vapor is condensing out in the line to the air brush. You’ll want to install a desiccant, in-line dryer just before the air brush to remove all… Read more »
Thanks I’ll give it a try before I throw it in harbor freights parking lot. I knew I should’ve spent more in the first place.
That there may be water condensing in the line has nothing to do with the make or model of air compressor, only with the temp of the air coming out of the compressor, and the temperature of the air that is surrounding the air hose, as well as how long the air hose is.
i bought a CP comp pump from harbor freight and was going to put it on a Campbell Hausfield tank.. The air valve from the pump to the tank did not come with a fitting or hose. thinking it should be a standard thread. Hook up the CP pump has a completely different thread and I can’t get a thread to match. A compression fitting thread , a pipe thread or any standard 3/4 thread… Read more »
Victor, I would surmise that the fittings on the CP pump and compressor are metric, but not sure about that. I don’t know of any “air valve from the pump to the tank”. There should be a tank check valve in the fitting where the line from the pump enters the tank. Not sure what you mean by “the pump does not come with any hose hook up parts to the tank”. Harbor Freight carries… Read more »
I picked up a 21 gallon for a dime, understanding the last owner was frustrated with it. Leaking, won’t build up pressure, etc. I can fix almost anything. The short version; the regulator was cracked, it actually fell apart in my hand, which explains the leak, the pressure line to the regulator is connected with the wrong fittings. I had to retro-fit other pieces salvaged from other dead compressors, pressure gauge doesn’t work properly, wrong… Read more »
Model 61454 21 gal 2.5 hp tries to start and quits. Hit reset will try and quit again
Daniel, I’ve uploaded an image of the compressor in question.
This is obviously a new issue, yes?
Any change in power supply of any kind?
Using an extension cord?
If none of these, please empty the tank and try again. If it starts OK with the tank empty, check that the unloader is working when the pressure reaches cut out will, and advise what’s what. If you aren’t sure what that is, see the unloader page on this site.
willyr, Mine Looks just like your picture, and I’m experiencing the same problem. Only my model # is 67847. I found that if I drain the tank down to 30psi or lower, it will kick back on without tripping the breaker. yes that is a PITA waiting for it to refill in the middle of a project. I had thought that the capacitor was going out, but the unloader does have me wondering. A link… Read more »
It is linked from the troubleshooting page on this site.
I have the exact same compressor with the exact same issue. At the very top of the compressor there is a brass nut with a brass pin that pops out when starting the compressor. Most of the time the pin either does not pop out letting the compressor run and sometimes the pin pops out all the way keeping the compressor from running this then trips the breaker on the compressor. I cannot seem to… Read more »
Google “cold start valves for compressors” and I suspect you’ll find what you are looking for.
I have the same problem with mine.
I bought a 6gal 150psi pancake compressor (oil-less Central Pneumatic) from Harbor Freight a few years ago and if I have 15 hours on it I would be surprised. Kinda why I took a chance on a Harbor freight model. Just in a location I don’t have a ton of need. Figured what little i’d use it it should last a bazillion years. It has developed an internal issue. Sounds like it’s “oil less” or… Read more »
Scott, have you pulled the cover off and run it to have a look? Assuming it is oil lubed, you’ve checked the oil, yes? Not using an extension cord? Have you tried using it in another location with a different power supply?
These compressors are the biggest waste of money. I don’t recommend this brand what so ever. There is nothing good about them. Straight pile of s**t.
CP 69667 * 10 gallon 2 HP Air Compressor* Air compressor starts but won’t build up pressure and then trips out on thermal. I changes the start valve as that was broken but no change. I can get it to work by disconnecting the air line from the T fitting for a quick second and then reattaching it. The compressor loads up but once it turns off at 125 PSI it won’t turn back on… Read more »
Sure. Have a look at this page Paul, and see if that’s the issue, will you?
First time use on my 3 gallon pancake compressor. Used it on impact gun. It blew a fuse which I replaced with the exact same size. Now the compressor will not turn on. Tried different outlets and nothing. Checked the fuse again and nothing. Is it toast or am I missing something??
You need to use a multi-meter to trace the power from where it reaches the fuse, and then trace it after the fuse to see where it goes. If it stops at the blown fuse, there may be an issue with power supply but if the power is getting past the fuse, where is it stopping? If it’s getting to the motor and nothing happens we need to know this. Please advise.
Hi willyr, thank you for the quick response. I’m not that great with eletrical work. How exactly do i trace the power with a multi-meter? do i need to take the top black cover off and get to the motor? do i need to find wires to test?
You need to use the multi-meter on the live wires at the various terminals on the compressor to check the presence of the correct voltage. Yes, you will need to remove protective covers to do so. If you aren’t familiar or comfortable with the process, I’d suggest you find someone that knows how, as dealing with electrical power incorrectly can be life-threatening.
Thank you. I can handle the basics. I was able to replace all outlets in my house but i killed the breakers before hand lol. i can handle the live wires safely it’s just a matter of know what and where. If the power is indeed getting to the motor and nothing is happening, does that mean the motor is toast?
When I’m working on any power project at home or shop I always kill the feed from the breakers too. That’s just common sense! Start with the power cord to the compressor. I suspect it goes to the switch? Is power at the switch, is power on the other side of the switch when it’s on? Same for the pressure switch, trace it to the motor. If power is there then trace to the fuse.… Read more »
What type of screw head does m6 30 screws have on the recessed top cover of the Central Pneumatic 1.5 gal. 6hp. ? Thanks
Are you sure this isn’t a 1.5 HP, 6 gallon air compressor? Typically this will require an extended metric Allen key I believe.
I have central pneumatic 1.5 hp 6 gallons air compressor,can”t found aluminium hose that connect pump to air thank.If anybody know where I can buy,please let me know..
Take the old hose to a plumbing supply house and ask them to make you one in copper tube. An industrial plumbing supply should be able to emulate the fittings, and should be able to help. After market pump parts for Harbor Freight air compressors seem few and far between. Good luck.
I have this compressor and it has run find for what I used it for but now it comes on and gets air but will not fill the tank or pressure up I have taken all pars off and made sure there are no clogs and still I get air but does not pressure up or show on the gadges
It runs and gets air you say… but it continues running and won’t fill past a certain pressure? When you say you have taken all the parts off, does that include the pump head to check the valve plate. Odds are pretty good that it’s either that or the piston ring that’s failing if it will run and run and not build pressure.
What is the procedure for replacing the piston ring, and can a do it yourselfer handle it. Where do we get parts?
The parts are probably the real issue, Dennis. You might try googling “parts for Central Pneumatic and your compressor model number to see if any are available. If not, then you’ll have to measure the existing ring carefully, and search for rings of that dimension. As to complexity, if it’s out of 10, I’d say 6 or 7 as the pump has to be torn down to get to the piston.
21 gal 2.5 horse motor no real use. When you start it it wont kick on all the way. Plugged it in to different places same result. Was told capacitor was bad replaced it an workes great for 10 minutes tried again and same problem it is also getting really hot. Ideas?
What does it mean that the compressor will “kick on all the way” It starts, or it doesn’t normally. With the tank empty of air, please power it up again, and let us know what does or doesn’t happen.
I need a set of brushes for a CP pancake air compressor Item# 61625 . ,6cfm @90psi
Can you tell me where to purchase?
Thanks
I believe that the electric motor brushes are specific, but not necessarily compressor brand specific as the motor manufacturers make compressor motors for so many different brands, though many have the same motor. If you Google “replacement compressor motor brushes” see if you can find them in this manner, since you’ll not likely get them at Harbor Freight.
I have a central pneumatic. Flip the switch pumps a few times & turns off. Got it about two weeks ago running beautifully. Now this Thanks let me know. Jim
Model number? Always had it plugged into the same outlet? In the two weeks, did you run it a lot? Is there anything else drawing power from the same power plug as you have the compressor plugged into?
My 6 gal 1.5 hp will run and fill the tank to about 145psi then it kicks the pressure relief valve open instead of simply turning off. I’ve had this a couple of years but this is only the third time using. First time it worked like a champ, filled to 150psi as advertised and shut off. The 2nd and 3rd time a no go. It just kicks open the pressure relief and keeps running… Read more »
If the normal cut out pressure setting is 150 PSI and the PRV is cracking open at 145 PSI, it’s likely the PRV that’s the issue. You can – with empty tank and compressor off – remove the PRV, rinse it in boiling water, let it dry, pull the ring a few times to be sure it can still cycle, reinstall, fire up the compressor and monitor it or, if that fails, replace it with… Read more »
Thank you willyr. I’ll give it a try. I’m new to compressors and wanted to purchase a lower end model to see exactly what I need before spending more money. Ironically, in the past I’ve got a lot of mileage from Harbor Freight tools with a little care and on occasion some modification. Thanks again!
I have a 1.5 horse 6 gallon Central Pneumatic air compressor model#62380. It has worked fine up until today. When turning the plastic covered switch to the on position, it lights up as it would normally, however now the compressor is not kicking on when it gets low. In fact, I emptied the tank and it’s a no go. Any suggestions as to what the problem may would be helpful as I would like to… Read more »
Good that the power is getting to the switch, Chris. And good that it lights up the on button. Question is, is the power getting through the switch to the motor circuit. Use a meter with the cover of the switch off and with great care and the power on, trace the power to the switch, to the ON/OFF button, and make sure that power is actually getting through the ON/OFF indicator light to the… Read more »
shuts off after a few seconds.Have to drain air completly before i hit reset button.Finally wont do anything.Motor ran good though.
Bob, are you using an extension cord now and weren’t before? Have you relocated the compressor? What it sounds like is that the motor is overheating and shutting itself down before damage can occur. An empty tanks make the restart easy. A full tank means back pressure and a harder start. If there is an unloader valve, make sure that’s working. If it is, and the compressor is plugged directly into a wall socket, and… Read more »
Unsure of the actual model but it’s the 20 or 21 gal virtical HF air compressor. When I plug it in you can hear the motor hum. Then the circuit breaker trips on the motor. I have the drain valve open. Thinking I have a bad circuit breaker on the motor itself. It has only built up air maybe 5 times since I bought it and always had to drain the tank every time to… Read more »
Are you using a power bar or extension cord to power the compressor? If not, what is the amperage of the circuit into which you are plugging the power cord?
Plugged directly into house on a 15 amp circuit. I have no problems running my welder off of a 50 ft drop cord off the same circuit but the compressor won’t run being plugged directly into it
Thanks for the reply. The humming is indicative of either a stalled motor (pump cannot turn so pump sheave and motor cannot turn as a result) or the power supply to the motor is in question. If the power supply from the power cord to the pressure switch, and then the pressure switch to the motor is good, then it’s the motor and that typically points to a start capacitor on the motor failing. By… Read more »
Sorry I wasn’t home with the compressor at the time. It’s a 2.5 hp 21 gal HF compressor. The compressor turns free. I just plugged it in and tried it. It will turn over about 3 times real slow then blow the on board circuit breaker
So I’m guessing start cap then.
Thanks. I was kinda leaning that way. I messed with it a bit today just flipping the switch on when I would walk by it. It got to where it would run flawless for 2 seconds the. Pop the circuit breaker. After that three or four times it started running great. Won’t build air unless I drain the tank completely and other times as long as it’s down to 50 psi it will run fine… Read more »
Is the run cap available?
John, it’s pretty hard to be specific about a run cap if we don’t know the model number of your Central Pneumatic air compressor. Different ones have different motor sizes, and that may affect the run cap specifics. Do you have the old cap? Can you see the voltage and micrfarad rating for that one, usually stenciled on the side. Any run cap with that same rating will work as long as you can get… Read more »
I have a Central Pneumatic air compressor that I acquired used. The model number labels are gone. Before I attempt to make new gaskets for the pump head, I would like to know if these parts are available. It is a 110V, direct drive, OIL lubricated compressor with single stage, single cylinder compressor pump. It is about 20gal and vertical. Cylinder head is aluminum, cylinder is cast iron. It has a steel plate containing a… Read more »
Daryl, if you haven’t done so already, Google “reed valve kits” then “Central Pneumatic reed valve kits” and then “Harbor Freight compressor reed valve kits”. I found a bunch. You might get lucky and find yours.
I found a kit that looks identical in design. Not certain about bore size and bolt spacing. . . do you know if Central Pneumatic ever utilized the same compressor pump as Campbell Hausfield? This is the reed valve kit in question: https://www.fix.com/parts/compressor/campbell-hausfeld/fix10243074/valve-plate-kit-hl026100av/?Source=GAWS%3fSource%3dGAWS&gclid=Cj0KCQjw4qvlBRDiARIsAHme6ouwrYROpYNgH0Thhyfea5GD2AmSb9gOvAaSp5usD5ZJESCQniO4EbwaAtl4EALw_wcB Meanwhile, I’m going to attempt to translate the grid scale to see if the bore and bolt spacing are the same.
Daryl, sorry for misreading your original post. I’ll get this up so that perhaps someone can tell us if Campbell Hausfeld made your compressor.
No worries, your suggestion was spot on. Thanks again. A little more googling and it appears to be the same compressor pump/motor assembly or a knock-off of the Campbell Hausfeld HL4000 series. . The Harbor Freight compressor in this video I found is identical to mine https://www.youtube.com/watch?v=RSwXKDg4hVg
I purchased a Central Pneumatic / Harbor Freight 61454 compressor about 1 year ago. Ran it when I first got it, then it sat for a year. Today I ran it and it filled fine (125 psi). Then ran the air down to about 90 psi and the compressor wanted to start then just hummed. I turned off switch. Drained tank to zero and compressor would start and fill. Drain air down to about 90… Read more »
I guess you changed the location of use of the compressor? Are you using a power bar or extension cord? Have a look at this page too: https://fix-my-compressor.com/compressor-wont-re-start-when-air-is-used/ and let us know if the unloader valve is working as it should, okay?
I was able to relocate the compressor and it seems to be working ok now. I am guessing it was a power issue even though it wasn’t popping any breakers. It now cycles normally. Thanks
You are welcome, and apologies for mixing up the replies.
model 10 gal 2.5 hp 125 psi. started it today and the oil shot out through the oil relief plug. Any idea what would cause this
Has the compressor been tipped over? Has there been a recent oil change? Is the compressor taking longer than normal to come up to the pressure switch stopping pressure?
No on oil change and it has not been turned over. Pressure was at 90 when I turned it on
I have oilless airbrush compressor. It stops and jumps around now. Not much air coming out of the regular. After jumping around, it then stops for a few seconds and then starts jumping again. What is the problem?
Linnie, while you know exactly what you mean, I’m afraid I don’t. What does “jumps around now” mean please? Are you saying the compressor starts and stops too often?
I take it this compressor has no tank, is that so?
When this is occurring, are you using the compressor for long periods of time at one sitting, and are you using any extension cords or power bars to get power to it?
What does it mean when my gauge needle won’t pass the 20 psi
Jason, please tell us what model of Central Pneumatic / Harbor Freight air compressor we are talking about, and which gauge… the tank or the regulator?
No power. Won’t even turn on. Model 100 psi 1/3 Hp 3 gal tank
Tank empty of air? Power at the plug? Power from plug to compressor? Power after the pressure switch, indicating that, with the tank empty, the switch is now “on” and passing power to the motor? Need a bit more info to try and further diagnose the issue, Joy.
Where can I get parts for 3gal. Oilless need a piston and sleeve, It’s about 5 years old.
I have a central pneumatic 125 psi 21 gallon model number 61454. It will come on build up to 40 psi and shut off, hit reset button and comes on for a few seconds before going back off. Just replaced pressure switch, any suggestions as to what the problem could be, can bypass reset button and it continues to run.
Becky, tell me, are you using an extension cord or power bar? If so, don’t. Plug the compressor right into a wall socket, will you? Did that help? Running the compressor while bypassing the reset button may be causing some motor harm. I guess you’ve got a power supply issue, and if it is not the use of a too-small extension cord or then the motor capacitor may be an issue. The issue is, I… Read more »
I don’t see the image, but it is plugged into a wall socket and not extension cord. What is the fix for the overheating
Well, the image upload didn’t work. 🙂 I think you’ve got a motor capacitor issue. “Start Capacitor The electric motor usually has a quick-discharge battery on it called a start capacitor to help in starting. If the start capacitor has failed, it is not giving the electric compressor motor the added boost necessary to get the motor going. If the other remedies have failed, then the odds are improving that the start capacitor is at… Read more »
It will start but won’t stay running and build pressure
Yeah, same answer as before I’m afraid. Harbor Freight are still selling these. Is yours fairly new? If so, talk to them too.
Thank you for all your help, we will try this
been looking for days now for 3/8 24 to 1/4 npt adapter/reducer so I can put an accessory in line with this regulator I have. any one know where?
Any of the big box stores Ace hardware any local hardware store should have a a bushing a 3/8 to quarter inch bushing
;I dropped my unit (#62380) and it landed on the quick-coupler, snapping off the coupler AND the piece it threaded into. The piece is a pot-metal construction that the pressure gauges and knobs all tie into. On the parts diagram the quick couple is Number 34. It appears that I would have to remove the entire assembly, gauges and all, just to get a new piece for the quick couple to thread into. then there’s… Read more »
I’m curious of the intake air flow on the 1.8 oil-less compressor motor.
Please that is.
And hokE, I’m curious as to how come that information is of interest to you? I’m trying to conceive of a reason, and cannot think of one. Perhaps, before I spend a lot of my time researching the issue – since I, and I suspect no one – knows the answer right off, care to let us know the how come?
Oh easy. Sorry.
I’m going to hook up an oxygen concentrator to it.
Basically making a very small on demand system for a torch.
Okay, let’s see what we can dig up, and for sure, I hope that another visitor with some information on this can chime in.
I need new air filters for my air compressor can’t find the size 1 3/8 tall 2 3/4 OD 13/8 ID where can we get them. my compressor is 5 years old still works fine
Hey Ryan. If you don’t mind visiting one more page on this site, this one talks about getting a new air intake filter. Let us know if this helps, will you?
I bought the Central pneumatic upright, model #47065. When I first started using it, it would charge up the tank as expected and then cut off as expected, so as not to over charge. However, after a little use, the compressor began popping the motor in-line reset switch at lower and lower pressures (after resetting the switch each time). The compressor is on a designated circuit and has never tripped my breaker. So, I pulled… Read more »
I’ve uploaded a photo of the 47065 to help folks regarding parts. Meantime, if you Google “compressor motor reset switch” you’ll find a bunch for sale on ebay. The issue is whether they are the same setting as the one off the 47065. Good luck with the search and if you find one, maybe you could post and let us know where
I have a central pneumatic standing portable 21 gallon 2.5 hp 125 psi single stage air compressor, harbor freight item # 61454 (not sure if this is model #). This compressor is brand new. Brought it home, drained shipping oil and flushed with provided oil to remove any slag from machining process. Filled halfway up sight glass with straight 30 weight oil, plugged in and flipped switch. It buzzed for about 10 seconds and tripped… Read more »
The manual states that the power supply be 120VAC / 60Hz / 14A (Dedicated circuit recommended). I surmise that the inrush requirements of the compressor, coupled with it’s distance from the power panel, contribute to the motor pulling more amps than the circuit can handle, and the breaker trips. Try plugging the compressor into a socket as close to the panel as possible, with nothing else pulling power, and see if it starts OK.
How do I remove the black plastic cover on the HF 6 Gallon 1.5hp oil-less compressor model # 62380. Am fighting a leak problem but need tp get at the guts to continue my troubleshooting.
Thanks in advance for any help you can provide.
Their are five M6 x 30 screws located in the recessed holes in the top of the cover. You’ll need an extended metric bit to reach them.
See the holes but no heads on screws. Seems like they are coming up from below.
Help !!!!!!!!!!!!!!!!!!!!!!!!
David, the manual, which you can get directly from the CP / Harbor Freight website, shows that, for your model, the screws are in the top. Maybe contact them if the manual is wrong?
Hello, I have a Central Pnumatic 60 gal. 5 HP 165 PSI Two Stage Air Compressor. this morning when I turned the switch on it started for 1/2 a second and shut down. I checked the fuse box at the house its was still on. I tried the empty the tank to get the pressure switch to activate the power on sequence with no effect. I just checked the motor and compressor both turn freely.… Read more »
A few pages linked from here: //fix-my-compressor.com/air-compressor-problems-and-fixes/ address this issue. Good to empty the tank as a first step. No success there, trace the power flow from before the pressure switch to the motor circuit. All good? Then see if there is a capacitor on this compressor motor. If so, check that. See how on the page on this site.
Hi. I have a similar problem with my new central pneumatic 60 gal. 5 HP 165 PSI Two Stage Air Compressor wouldn’t turn on after pressurizing and cooling. Do they have a capacitor? Did you get a fix?
Since there are so many postings on this Central Pneumatics air compressor page, I’m having trouble determining to which you are referring, David. In order to further qualify the problem you are experiencing with your compressor, can you tell me please, after the compressor reaches the normal cut out pressure setting and stops, is the unloader valve actually operating?
I have the 21gal upright compressor and have had it. I knew going in you get what you pay for and it’s worked “ok” for a few years. Recently it’s started to fail on re-start. It’ll get up to 125psi or so when empty but as I use it, when it kicks back on it chugs once or twice, humms and quits, popping the fuse. From my understanding it’s the unloader valve(?). I’ve looked everywhere… Read more »
Could be unloader, could be start capacitor, if no change in where you use it or the power supply. These are, in my opinion, “light duty” air compressors, and are suitable for hobby shop or home workshop intermittent use. Cheap to buy, expensive to maintain. If you need compressed air on an ongoing basis, moving up a quality notch might not be a bad idea.
I have a central pneumatic air compressor model #94667 which has quit pumping higher than 45 psi, so it never cuts off. I have to shut it off to keep it from running constantly and burning up. What may be my problem and can I repair it myself?
This may help, David: //fix-my-compressor.com/when-an-air-compressor-runs-and-runs/
When you’ve done the checks, add a comment if you need a bit more help.
Mine did exactly the same thing. I took it apart and the piston ring was broke. I’ve looked all over and can’t find a replacement.
If you haven’t measured the broken ring, and simply Googled “piston ring with xxxx dimensions”, you should. Someone is making the rings and you should be able to find a non-OEM version.
I have the 29 gallon 2hp compressor. It’s oiled and has a motor from marathon electric in Wisconsin. I did the cfm calculation and it’s giving me 7 cfm on refill from 120psi to 150 cut out. Don’t know how accurate the formula is. Also used my clamp ammeter and found it to spike to 26 amps on start up and runs at 14.9 amps while running. Recently it started clicking. Can’t tell where it’s… Read more »
No idea where the clicking is coming from, Chris?
I wonder if it may be the centrifugal switch, if this motor has one and the clicking may be a warning of the switch gunked up, weakened to the point of failing, or burnt?
I have a harbor freight air compressor that I purchased used.. it’s a stand up 21 gallon rather 150psi. The tank only builds about 80psi and the the prv pops and starts letting the air out?? I thought maybe the pressure gauge was reading wrong, but tried using my air gun to remove a lug and it does not have enough psi to do it.
When you say Harbor Freight air compressor, I take that to mean a Central Pneumatic product? If not, please advise. A quick way to check the gauge is to swap the tank gauge with the regulator gauge and see if the same discrepancy in PRV cracking remains, or that it was the gauge that is failing. If it is for sure the PRV that’s cracking early, with the compressor off and the tank empty, remove… Read more »