Hey! This site is reader-supported and we earn commissions if you purchase products from retailers after clicking on a link from our site.
by Omar
Hello my compressor Kobalt model 0332041 20 gallons won’t build enough pressure cut out pressure is 150psi and cut in is 120 psi
i just replaced pressure switch but it does the same thing.
Just build pressure to 50 psi and doe not restart I have to shut off ……drain all the air and start again and does same thing just go to 50 psi and does not turn on.
Please help I was trying to find something at the web but there is nothing about this compressor absolutely nothing Please Help Me!!!!!!!!

_______________________________
Kobalt 0332041won’t build enough pressure
Howdy. My friend this issue is well covered in the troubleshooting pages on this site. Please see:
Air compressor won’t stop running
https://about-air-compressors.com/compressor-why-not-build-pressure.html
If these don’t help, please add a comment telling me what you have checked and what you found.
________________________________
Kobalt compressor w/build pressure
I had the same issue and it was the extension cord. I was using a 100′ cord and the unit would build pressure to about 50psi and then start bogging down and shut off. I went back to my electrical training and remembered high amperage draw units are finicky when it comes to the resistance in long cable runs (100′ extension cords). I plugged it directly into the outlet and no issues since. If you must use an extension cord, use the shortest possible.
New comment? New question? Please add it here along with photos to help others help you with your compressor and equipment problem!
SORRY SAME PERSON WITH KOBALT 20 150PSI THAT BLOWS PRESSURE VALVE AT 115PSI AND THE MOTOR KEEPS RUNNING. IN ORDER FOR IT TO STOP I HAVE TO USE THE ON/OFF SWITCH.
This sounds like the pressure switch is bad. Here is the manual with the parts diagram.
http://pdf.lowes.com/useandcareguides/840534000059_use.pdf
Just be careful ordering pressure switch off the internet, the threads and PSI on/off are different for all of them.
Alton Industries builds these units and you can order straight from there.
I have a kolbalt 20 gallon 150 psi cut off and 120psi start up. My problem is it will build air up to 115 and blow the relief valve. It has done this since the day i purchased it. It has noway to adjust the cut on and cut off its a pressure switch that screws into the tank. Please any help it would be greatly appreciated.
If you bought it new, it should have gone back.
I’d remove the the PRV, check the rating, usually stamped near the threaded end. It should be rated about 160psi. If it is, try cleaning it, let it dry and try it again.
If it still blows, or is stamped less than 160psi, look for a new one rated 160-170psi.
160 psi might be marked around 11.(something) bar.
Hi there, Exactly the same problem (stops at 50lbs) with my Kobalt air compressor (same model). I also replaced the pressure switch and still the same behavior. I notice if I let it set and cool off, unplug and then replug it back in, it will go another 50 lbs to about 100 lbs of pressure, but then shuts off again. So, the comment about a heat sensor seems to make sense. It’s running until it gets to a certain temperature and turns off. I am looking at a blow-up diagram of the compressor and nothing is labeled as “heat… Read more »
I confirmed last night that it is related to heat. I was evaluating the check valve and while I had the transfer tube disconnected, I turned on the compressor. It ran like a champ for as long as I left the switch on. The head of the compressor was not nearly as hot as when the transfer tube is connected to the check valve. How hot are those things supposed to get? The check valve seems to work. The spring and the rubber are fine and once I get the tank up to pressure, it holds the air. Am I… Read more »
Right. And it’s not on the parts list. You may be able to ID and replace it by disassembly.
From the manual:
Thanks Doug. I am changing out the transfer tube because the diameter on the current transfer tube is very small (4mm) and creating a lot of resistance. (Since I am not the first owner of this compressor, I’m suspicious that the transfer tube has been replaced with an inappropriate size tube.) And I am changing out the check valve since it’s the only other thing creating resistance and it seemed to be making more noise than I would expect. If those work, then maybe the motor will not heat up as much. Your idea is the next step. I’ll post… Read more »
If the check valve is making noise, it may just need a cleaning, rather than replacement. Your choice of course.
Have fun.
Had the same problem with it shutting off at 50 PSI. Found problem. Look in the back of the for a small (SCARE OVER HEAT SENCER)… something over heat sensor (moderator) there’s two wires connected to it that, cut that off, and I put a reset button type (TYP?), works fine now.
(Some editing by moderator to make it a bit easier to read. Hope I didn’t change the message incorrectly. )
I have the same problem. I always plug directly to the same dedicated outlet. I can get to 150psi on startup, subsequent cycles cut off earlier and earlier. No apparent leaks. Unloader does leak during compression. It is just a pinhole unloader valve, is it supposed to pass air during compression or is that my problem. It does not leak after discharge, so check valve seems fine.
You mean the motor quits before it reaches 150?
Check your run capacitor. It may be going bad, causing the motor to overheat.
Thank you. I tested the RC after posting. It read faulty. Ordered a new one. I will update when I replace it next week. Thanks again.
It was the run capacitor. Thanks for the suggestion. Took till now to get one. Be careful, Home Depot has the perfect replacement on their website. 3 times they sent the wrong one that did not match the picture or description from the website. I ended up getting it off ebay.
Three times, eh? Could you tell if it was the same one, or a different one each time?
Anyway, thanks for reporting back and glad to hear you got it fixed.
It was the same one. I told them to write my name on it as I think I got the exact one 3x’s(50uf instead of 60uf with different connections than the picture on their website). The clerk dropped it the second time and the third time, one of the posts was bent.
Wow. Sloppy.
Thanks for the heads up on that.
Did you find resolution for this? Ours (same compressor) is doing the exact same thing.
Have you checked the sources listed? In other words, do you have any idea what is NOT the problem? Please check and advise.