Author Topic: Yong Heng Deader than a doornail.  (Read 1051 times)

steveoh

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Yong Heng Deader than a doornail.
« on: June 08, 2019, 08:55:09 AM »
Yong Heng Deader than a doornail. Was just filling a tank before it gets too hot. 45 minute tank was up to 4100 psi and I thought I heard something strange. I bled the moisture off and let the compressor shut down. Poked around, and turned compressor back on with bleed valves open, ran for half a minute, tightened them down and then all hell broke loose. She is toast. Sounds like metal on metal hammering.

These things often blow out a piston. Will take apart and see if I can just replace the whole top end, and get it back to running. Otherwise I’m back to filling up at the fire extinguisher place. Damnit.



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steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #1 on: June 08, 2019, 10:05:22 AM »
And yep. Catastrophic failure. Piston destroyed.

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steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #2 on: June 08, 2019, 10:17:50 AM »
Looks like a mess. Rebuild or cut my loses and steal money from my kid’s college fund?

Gah!
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Frank in Fairfield

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Re: Yong Heng Deader than a doornail.
« Reply #3 on: June 08, 2019, 12:43:26 PM »
I think I saw a youTube video Steve on how to rebuild the whole top-end..
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Capt45

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Re: Yong Heng Deader than a doornail.
« Reply #4 on: June 09, 2019, 09:05:34 AM »
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steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #5 on: June 09, 2019, 10:00:04 AM »
That was a good video. I hadn’t gotten to the point of removing the reed valve.
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caniborrowsomeammo

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Re: Yong Heng Deader than a doornail.
« Reply #6 on: June 09, 2019, 09:24:44 PM »
That piston top doesn't look very thick Steve. I just wonder if it would interchange with a piston on one of the many Chinese engines out there.
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steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #7 on: June 09, 2019, 09:37:30 PM »
That piston top doesn't look very thick Steve. I just wonder if it would interchange with a piston on one of the many Chinese engines out there.

The pressure piston bolts on top of this piston.

I’m willing to bet that a tiny bit of upgrades would make these things reliable.
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caniborrowsomeammo

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Re: Yong Heng Deader than a doornail.
« Reply #8 on: June 10, 2019, 01:22:04 PM »
Cast some aluminum to the underside of the piston, maybe????
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steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #9 on: June 10, 2019, 01:39:45 PM »
Some feller on Facebook says that one of the Yong Heng clones uses a a single seal high compression piston, and that it doesn’t kill the big piston.
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Alan

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Re: Yong Heng Deader than a doornail.
« Reply #10 on: June 10, 2019, 02:14:14 PM »
I guess we're taking a chance on the one I shipped to you as well. I didn't buy the extra-cost warranty, but perhaps I should have. The truth is, we don't know who makes all of these new, dual-voltage compressors. The power supplies, built in with the compressor or stand-alone, are stable devices for the most part, as billions have been made.

The compressor part appears to be the same. I've seen the insides of three different brands, and the (nominal) 12 volt motors look like they came from the same manufacturer. The compressors look close enough to be from the same manufacturer, or a least a clone. This brings up an interesting issue.

Based on the shipping method, and estimated delivery times, the unit is being shipped from someplace in China. Yet, it has the same features as those with US-brand names on them. At half the price yet! Only time will tell how good this off-brand is. If it lasts as long as most Yong Heng have, it might be time to start a Christmas-Club account at the local savings and loan!

Lastly, the Benjamin Traveler I suggested my shooting buddy to buy, has ran flawlessly for several weeks. It has filled several small bottles, even though it is not supposed to be used in that service. We shall see.
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Alan

I have an Omega compressor. If you're a fellow Guild member, and you pass through Roswell, NM, I'll fill your portable tank as a courtesy.

steveoh

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Re: Yong Heng Deader than a doornail.
« Reply #11 on: June 24, 2019, 06:54:58 PM »
I got a new topend for the Yong Heng. Trouble is it was damaged in shipping and broke flush one of the bronze/brass nipples for the cooling hoses. I beat on that thing and heated it but could not get the recommended Allen wrench or my own idea of using a star wrench to get the broken part out. Finally went to Harbor Freight and got a set of pipe sized easy outs. Hammered a 1/4” easy out into the brass, and then while under a bit of pressure trained a propane torch on it. After a few minutes I got movement. I’d turn a bit, reheat, turn some more and repeat. Finally got it out.

Put the whole mess together, drained the old compressor oil, and put in fresh.

Ran the compressor gingerly a couple times with bleed valves open, and let it cool down. Ran for another five minutes same way, let it cool down. Ran it again but then closed the valves and squirted soapy water around all the pipe and thread joints. Two major leaks on the new stainless hoses they sent. They were incorrectly crimped.

Put on old hose and I’m back in business.

Up next take apart the 12volt compressor and see if I can fix the three leaks it has. I am pretty sure I’ll need parts.
« Last Edit: June 24, 2019, 09:59:33 PM by steveoh »
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caniborrowsomeammo

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Re: Yong Heng Deader than a doornail.
« Reply #12 on: June 24, 2019, 08:21:59 PM »
You'll be a whiz bang compressor mechanic in no time. :)
Buncha BB guns that I don't get to shoot as much as I like. Grinding out a living on the farm.