Yong Heng help needed! - solved

[qball]

So my faithful little Yong Heng finally decided it doesn't want to go above 3000 psi after 3 plus years. So I ordered a second state piston which seems to be the most logical thing to replace. Opened her up and realized there is crack in the seal while the piston looked fine actually, so replaced seal and put everything back together. Nope, still won't go above 3000 psi. So opened her back up and replaced the piston. Put her back together and now it won't start with a buzz noise. Took everything apart again and everything seems to be just fine but before I put all the pipes back on I turned it on just to make sure the electric motor will spin but nope, just buzzing noise.

Pretty frustrating, make sure the crank easily turned, the piston go up and down just fine in the cylinder and added oil just in case but not working. Any ideas?

It sounds exactly like in this video.

 

[Gerry52]

Capacitor (starter motor)? I've got 2 sitting around. Being that I have a new YH I don't think I'll be needing them. I'll send em out to you if you want. PM me.
Note: pm'd you with my contact info.

 

[qball]

Thanks Gerry52! I kinda know the issue now and I also realized I made a big mistake!

So I took everything apart again, add more oil the piston orin and made sure it is moving ok. Before I put back on the pipes I turned on the switch and it ran. Button everything backup and hook it up to test pressure and back to no start and buzzing sound. Then I took off the cover and man the fan is stuck but with some wiggle I got it turning a bit and flip the switch and it's running. Long story short I went back and forth and left the cover off just so I can test pressure.

here is where I realized I made real big mistake! It still won't fill to 3000 psi!!! WTF! So I flipped the switch off with pressure in the system to see where the leak it. And found the most stupid and embarrassing leak......the Fooking GAUGE!!! So I went through all this trouble and broke my compressor because I didn't realize I need a new gauge!!! So still need to figure out why it's sticking at some point in the cycle, once it's passed that binding spot the compressor seems to run just fine! This is really embarrassing, granted it's about time I rebuild it anyways but internal parts actually look surprising good. Now I need to wait for a new gauge and start the self inflicted pain again!

 

[WorriedMan]

Pulled high pressure "top hat" on mine, too, when pressure wouldn't rise, real problem was bad "O" ring in female foster fitting. (Cost me a new gasket.) Lesson learned, now use dead head plug and soapy water spray bottle to find leaks. Found leaking pressure gauge and Delrin seals using this method not long ago. Borrowed liquid-filled gauge from Chinese HPA handpump, screwed right in, works great. WM

 

[qball]

Update: borrowed the gauge from my and pump and tried pressure test again and BAM it got to 4000PSI in a hurry! I said screw it, hooked up my 60 minute tank and let it rip. Basically a little over 15 minutes from 3200 psi to 4100 psi, woot! Not only it worked great but it also seems a little faster than before so I feel better about tearing into a perfectly good compressor.

Also good news is once it ran for a while think the lub got to all the places it needs to be so it isn't having issue starting again. Fingers crossed it will start after it get back to cold but I'm hopeful. What a mess for a bad pressure gauge but didn't turn out too bad and got pretty descent at disassemble and reassemble the YH now!

 

[WorriedMan]

Update: borrowed the gauge from my and pump and tried pressure test again and BAM it got to 4000PSI in a hurry! I said screw it, hooked up my 60 minute tank and let it rip. Basically a little over 15 minutes from 3200 psi to 4100 psi, woot! Not only it worked great but it also seems a little faster than before so I feel better about tearing into a perfectly good compressor.

Also good news is once it ran for a while think the lub got to all the places it needs to be so it isn't having issue starting again. Fingers crossed it will start after it get back to cold but I'm hopeful. What a mess for a bad pressure gauge but didn't turn out too bad and got pretty descent at disassemble and reassemble the YH now!

Look at all you learned behind it, that's a silver lining, for sure. WM