Death of my Yong Heng

[Saltlake58]

It is with great sorrow that I announce the death of my Yong Heng compressor. It appears to have had a fatal seizure with critical parts malfunctioning. In other words, it was running, it shuddered, it stopped and hummed. I suspect the motor died.

While I am sad at the passing of my dear friend and compressor, must say it paid for itself in the past 9 months I've had it. tank after tank of air, on demand and saving cash every time I used it.

I don't intend to order another one just yet, might wait till next spring. With winter coming, using it in my area might prove problematic. Spring will fix all that again!

I'll begin the autopsy shortly, but for now, back to the paintball shop for air. Sad really, but Mr. Yong Heng worked his heart out, and it stopped. I'll miss him!

 

[cahil_2]

RIP!

 

[airgunfans]

Sorry to hear about that. The good thing about Yong Heng is parts are available at very low cost . The construction is relatively simple so trouble shooting is not difficult. Can you turn the fan by hand ? If you can do it with reasonable force then there is no seizure and the motor is probably burnt.

 

[Saltlake58]

thank you for the sympathy. I should be able to get it apart and diagnose cause of death in the next week or so. My bet is the motor because of the way it died. Just stopped, now it hums a monotone tune

Alibaba, here I come!

 

[Alan_B]

I'd guess a crank bearing failure. The motor is still trying, but the friction has gone way up. Or the starting capacitor has failed, or the starting switch.

If power is applied in this condition the motor may fail very quickly.

Can you turn it over by hand? That should help sort the possibilities.

 

[airgunfans]

The Yong Heng uses a capacitor motor. This is a trouble shooting guide for this type of motor. Hope it helps : 

https://www.fluke.com/en/learn/blog/motors-drives-pumps-compressors/centrifugal-thermal-and-capacitor-switches-cause-most-single-phase-motor-malfunctions

 

[Hepotter]

Didn't Yong Heng upgrade the piston because of too many failures on the older models? Contact them and you might get a repair kit and parts for cheap or even free.

The problem was the first stage piston was too thin and broke at the bottom. They upgraded the piston and shaft to correct that...or words to that effect!



Kind regards,

Uncle Hoot

 

[Jorgo]

How much working hours was on your compressor?

 

[airgunfans]

I'd guess a crank bearing failure.

Possible. There has been a report about the tiny oil stirrer on the end of the connecting rod breaking off resulting in cutting off of oil supply to moving parts and seizing of the connecting rod "bearing". Actually the connecting rod does not have any ball bearing or bushing but just a hole on the body of the rod, The aluminium of the rod rubs directly against the steel pin on the crank shaft so if there is no oil, seizure can easily occur. 

 

[Saltlake58]

Autopsy Results:

The motor, crankshaft and bearings are just fine. I could spin the assembly until it hit top dead center. Right before TDC, it stopped. I reversed, and it stopped right before TDC going the other direction.

Removed the cylinder head and pulled the top off. Bits of brass were all over the top of the piston. Looks like the top of the piston broke up into little pieces. the bits piled up on top and jammed the whole thing enough to stop it. Cylinder still looks smooth, will go out in daylight tomorrow and take a better look.

So, off to buy repair parts. Looks like a new piston assembly is required for this one.

Oh, and working hours is under 10 hours. Pretty pathetic, but whatever. I run it about 8 minutes at a time filling the 88 cubic inch bottles from 2500 PSI to 4500. Sometimes only to 4000. I'll drop Yong Heng a note and see if they get back to me.

 

[airgunfans]

.... the top of the piston broke up into little pieces. the bits piled up on top and jammed the whole thing enough to stop it....

This is the third or fourth time I see reports about the 2nd stage piston breaking up. I would suggest you to check the reed valve at the top of the 2nd stage cylinder as well. That piece of thin metal could have been deformed after being hit by the debris.

Photos source : 

https://www.airgunnation.com/topic/dang-yong-heng/

https://www.airgunnation.com/topic/yong-heng-8/

 

[Eaglebeak]

If it's only the very top that is damaged, it's a cheap and easy fix. $12.00 plus gaskets if needed. https://www.aliexpress.com/item/32863290524.html?spm=2114.12010608.0.0.2214673bqxw4ZU or for another 20 odd bucks, you could replace the whole piston and rod. 

 

[Alan_B]

Looks like it was attempting to compress water.

 

[Saltlake58]

Looks like it was attempting to compress water.

Hope that's not the case, I'm pretty good about bleeding the water condensate every 2 or 3 minutes. Next time, I'll be more diligent

 

[airgunfans]

It looks more like metal fatigue to me because of poor-quality metal. Unless the reed valve on the high-pressure side is blocked there is no chance for the piston to compress water. 

 

[Saltlake58]

whatever the cause, I ordered a couple of the piston ends tonight. Three weeks or so to get here from half way round the earth. Until then, compressor is down. Oh well, I guess $11 and down for a month is better than a new compressor.

At least these things are easy to work on.

Now, if I can just get all the parts back together when the parts come in . . . . . . 

 

[Alan_B]

Piston compressing, water condensing, water and air mixture trying to go through closed valve, valve opening. Peak forces sufficient to destroy metal piston. 

I would think piston, bore and valve are all suspect after the piston breaks. Replace as a set?

 

[airgunfans]

...Now, if I can just get all the parts back together when the parts come in . . . . . .

You may want to take the chance the replace the first-stage piston with the new version one which has got a thicker top hence less prone to breaking. You may also want to replace some of the O rings. The one on the check valve at the outlet is always the first one to break. It's hidden inside the compression fitting nearest to the outlet.

 

[Saltlake58]

The bore looks OK, so rather than spend the $50 to replace everything, I'll try the top of the piston for starters. Parts are on order, so by end of October, should know if resurrection is possible. Only time will tell