Need help with Porter Cable air nailer...

[MikeP]

I'm having a problem with my Porter Cable roofing nailer (RN175A). I just rebuilt the gun as it had air leaks everywhere. The air leaks have stopped and the gun fires great, ONCE. The piston won't go back in the cylinder every time it fires. Any ideas? I replaced the trigger valve assembly and all the o-rings. Is it possible that the trigger valve assembly only goes in one way? Or should I put more oil on the driver kit O-Ring?

[cmoorejack]

Hey Mikep,
Try more oil first..[not too much!]..you can also trying to reset the tool by keeping your trigger pulled,safety released..[no nails!] and then hook up the tool to your air hose..it should fire as soon as you do this and re seat everything.. you may also have to reassemble the tool a coupla times to make sure every thing is installed correctly..hope this is helpful..
Craig
Geneva Tool Repair

[MikeP]

Thanks. I'll give it a try and let you know how it goes.

[MikeP]

No go. Still fires once, then won't retract. I've taken the gun apart several times and reassembled. Any more ideas?

[cmoorejack]

Hey MikeP,
The only thing left is the head valve [part # 892774] and or the o-rings [part # 886085]..to test lay the top cap down face up and push down on the head valve..you should have some kind of resistance or a swishing sound..if not replace the o-rings and or the head valve..o-rings should be lubed with a light grease..
Good luck..
Craig