Been running Yong Heng for 8 months. It stopped building pressure and lots of air now comes out of the breather valve. I've torn down the unit and found that the tip of the 2nd high pressure (gold) piston was broken. I replaced the piston. Also changed a broken o-ring in the high pressure check valve. Fired up the compressor today and still have a problem with lots of air coming out of the oil fill breather valve. Any suggested solutions?
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Yong Heng Need Help Air Out of Breather Valve Not Building Pressure
- Thread starter hiro
- Start date
Is it possible you installed "leaf valve" (flat silver valve on top of LP cylinder) upside down? (#10 in diagram, next post)
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Replace the 'check valves'. Listed as #8 on the IPB, it's #10 as 'first stage valve shim' a metal flap that only allow for one way air travel. Also, you may be blowing air past the first stage rings.
If the first stage or second stage cylinder sleeves are scored, they will not hold pressure but since you are getting blowback, start with the first stage valves shown in the picture attached below.
If the first stage or second stage cylinder sleeves are scored, they will not hold pressure but since you are getting blowback, start with the first stage valves shown in the picture attached below.
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Wish it were that - but it’s not. Was extra careful to make sure I had the right orientation on the leaf valve when i put it back together. Thanks for the input
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Interesting - I found this thread which led me to the Second Stage Valve Base (part #6) on the IPB. Looks like the hole in my 2nd stage valve base has a piece of the tip of the pencil high pressure piston lodged in it. I had replaced the pencil piston since the tip was broken - looks like a piece of the tip got lodged in this 2nd stage valve base hole. I’ll try to clear the hole and see if this is the culprit on why I’m getting back pressure into the crankshaft and thus lots of air out of the breather valve.
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