Compressor won't build pressure past 50 PSI.

[Sonar Chief]

Need some help w my oil less compressor , I replaced both pistons, rings(seals), gaskets and o-rings and on start up it won't build pressure past 50 PSI.

I left a comment on the Sears tech blog ... no one has replied, anyone have a solution to this? I was wondering if the pressure switch is faulty, but how do you test the switch?

Any suggestions would be appreciated!

Michael

[samckitt]

I had one that did similar, It was the reed valves, one was broke off, so air was being pushed back out of the cylinder into the atmosphere, not in the tank.





Pic may not be exact one, but shows 6 little reed valves. Air is sucked in past them, but when compressed it seals & blows through a single valve.

Other side looks like:

[GregWeld]

SAMCKITT --- but then you're compressor ran non-stop but didn't make pressure --- Not sure if Michael is having that same issue or not.....


So Michael --- it it builds to 50 psi and shuts off -- sounds like either your motor is overheating and you're getting a thermal shut off --- OR your pressure regulator is acting up. I don't know how you'd test that.

[samckitt]

Originally Posted by GregWeld

SAMCKITT --- but then you're compressor ran non-stop but didn't make pressure --- Not sure if Michael is having that same issue or not.....


So Michael --- it it builds to 50 psi and shuts off -- sounds like either your motor is overheating and you're getting a thermal shut off --- OR your pressure regulator is acting up. I don't know how you'd test that.

Yes, ran non stop.

[Sonar Chief]

Originally Posted by samckitt

I had one that did similar, It was the reed valves, one was broke off, so air was being pushed back out of the cylinder into the atmosphere, not in the tank.

I inspected the reeds and clean what little dirt was on them and re installed, here are a couple pixs with the heads off and new gaskets and o-rings installed.




Pic may not be exact one, but shows 6 little reed valves. Air is sucked in past them, but when compressed it seals & blows through a single valve.

Other side looks like:
[/QUOTE]

Originally Posted by GregWeld

SAMCKITT --- but then you're compressor ran non-stop but didn't make pressure --- Not sure if Michael is having that same issue or not.....


So Michael --- it it builds to 50 psi and shuts off -- sounds like either your motor is overheating and you're getting a thermal shut off --- OR your pressure regulator is acting up. I don't know how you'd test that.

Originally Posted by samckitt

Yes, ran non stop.

My compressor also runs non stop ... just makes 50 psi and no more! There is air being sucked into the intake, ie. no blow by or restriction.

Greg .... how do I tackle this problem? Can the shut off switch be bad if the motor continues to run, don't make no sense!

Thanks for helping .... I need my compressor up and running!

Michael

[samckitt]

If air pressure only builds to 50 psi, & motor runs on & on, then air has to be escaping somewhere. Now that I think about it, I also had to replace the one way valve on the tank where tube from compressor enters tank. Maybe that is bad. Let it run until you get 50 PSI & shut it off & listen for air leak.