Compressor problem... opinions?

[IcyBishop]

Hey all...newbie here

I have a Porter Cable compressor (15gal, 4.5hp little guy), I use it every now and then to inflate tires, do car work with the impact gun, and occasionally use a grinder for odd jobs.
I've always kept it clean and opened the tank for the water to drain, but one day I turned it out and it didn't sound quite right... and the pressure would only build to about 60 or 70 psi.. if the regulator was set to anything above that the compressor would just stay on because it simply couldn't reach it. There's no leaks anywhere in the lines or from the tank.

Does the motor need rebuilt, bad regulator, or what?

Thanks for all the help!

 

[GearHead_1]

Could the pressure relief valve (pop-off) be stuck or the drain valve be open?

 

[MXtras]

My guess is puked-out reed valves. Yank the head cover or the head and look at the valves - clean them up and flip them over if they are reeds.

Keep in mind that I do not know your compressor exactly...

Scott

 

[IcyBishop]

the relief and drain are good.. operate normally.

I dont know my compressor too well either MX, but if there is a head on it I can surely remove it and take a look at things

 

[Brian]

Also sounds to me like broken reed valves. They are thin metal flaps that act as one way valves. After bending back and forth so many times they eventually break.

 

[l_bilyk]

I agree with what was said above. check the reed valve

 

[eschoendorff]

How do you guys torque down the head when you re-assemble it? Any particular TQ values?

 

[bmwpower]

How do you guys torque down the head when you re-assemble it? Any particular TQ values?

Not sure for PC, but for Craftsman compressors you can get the torques from their parts website.

 

[vjquan]

The PC compressors are made by Devilbiss. www.devap.com You can get the manual and parts breakdown from there, you just need the model number.
On my compressor, the head torque is 7 - 10 ft. lbs.