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All Springer/NP/PCP Air Gun Discussion General => PCP/CO2/HPA Air Gun Gates "The Darkside" => Support Equipment For PCP/HPA/CO2 => Topic started by: imadunatic on September 10, 2017, 09:54:11 AM

Title: Yong Heng Replacement Parts?
Post by: imadunatic on September 10, 2017, 09:54:11 AM
Anyone have links?

I know several have said they ordered extra cylinders, pistons, connecting rods etc. Most of what I find is for tuxing and I'm assuming these are not interchangeable? I think once I recover from buying the compressor I'm going to stock up on a few replacement parts before they disappear.

I think I found the entire upper assembly here: https://www.aliexpress.com/item/Electrical-Air-Compressor-Head-Cylinder-and-Piston-and-Cylinder-base/32786313580.html (https://www.aliexpress.com/item/Electrical-Air-Compressor-Head-Cylinder-and-Piston-and-Cylinder-base/32786313580.html)

Not terrible for the entire top end, remains to be seen how "bulletproof" the bottom ends are though also (Yes these little compressors are a gamble!).
Title: Re: Yong Heng Replacement Parts?
Post by: shultz on September 10, 2017, 10:12:16 AM
I ordered that head, it is correct for the yong heng.

I also ordered a complete, first stage/second stage piston, and, second stage seals for the jufeng compressor. I though it was the same as my yong heng. Nope, closer to the tuxing even though the pictures looked right. $30 mistake, I've made worse :D I still have not found the second stage seals or first stage piston or rings on Aliexpress for the yong heng.....

So, I contacted the ebay seller, nice-shop2, I bought my compressor from. Allen replied, once we worked out exactly what I wanted, second stage seals and first stage piston rings, he was able to order them from the factory and have them sent directly to me. cost $35 shipped for 6 sets of second stage seals and 2 sets of first stage rings. I had them in about 10 days.

John
Title: Re: Yong Heng Replacement Parts?
Post by: imadunatic on September 10, 2017, 01:26:20 PM
John,

It appears the head linked includes the pistons also, is it just a connecting rod stuffed in there for the picture? I will have to contact one of the vendors for the seals and rings when I get to that point.
Title: Re: Yong Heng Replacement Parts?
Post by: shultz on September 10, 2017, 03:15:11 PM
Yep,

That's a complete head. first stage piston, rings, second stage piston/seals, the whole top end. Simply remove the end of the stainless lines that connect to the compressor and the two bolts that attach the first stage head, slip the whole head off. It does help if the crank shaft is at the top of its stroke when removing the lower connecting rod end.

The new head, even included the paper gasket.

I changed the head on mine because I was worried about oil blow by on the first stage piston rings. I had about 10 hours of run on it. its wasn't really bad, just bad enough to worry me. The complete, new head went on without issue. I seated the rings for about 10 minutes at zero load. changed the oil. I have about 3 hours on the new head, very little, what I would consider a normal amount of oil blow by still.

I took a set of first stage piston rings and second stage seals, rebuilt my original head and have it boxed up ready to go when needed.

BTW, the yong heng uses a one piece, second stage seal with an O ring under it. Luckily, I had installed similar seals before. install the 3 O rings on the piston. Then, put the seals in HOT water, let them get a little soft and pliable. Used a small set of needle nose pliers to stretch them just a tiny bit, enough that they would slip on the piston without any damage. If you're not careful, you'll ruin a seal before you get it on the piston. Go slow, don't force them on the piston.

Once the seals are on the piston, it does not want to go into the bore. I again heated the seals(and piston) in HOT water. Worked them a bit with my fingers to conform them to the piston. Then shocked them in ice water, letting them completely cool. Now, they JUST slipped into the head. Again, go slow, a little wiggling/working of the piston will get the seals in without damage.

The first stage rings are easy. just be careful you don't snap a ring as they are hard and brittle. I did break the used middle ring removing it from the piston...
Title: Re: Yong Heng Replacement Parts?
Post by: Kmaz on September 14, 2017, 07:20:58 PM
Yep,

That's a complete head. first stage piston, rings, second stage piston/seals, the whole top end. Simply remove the end of the stainless lines that connect to the compressor and the two bolts that attach the first stage head, slip the whole head off. It does help if the crank shaft is at the top of its stroke when removing the lower connecting rod end.

The new head, even included the paper gasket.

I changed the head on mine because I was worried about oil blow by on the first stage piston rings. I had about 10 hours of run on it. its wasn't really bad, just bad enough to worry me. The complete, new head went on without issue. I seated the rings for about 10 minutes at zero load. changed the oil. I have about 3 hours on the new head, very little, what I would consider a normal amount of oil blow by still.

I took a set of first stage piston rings and second stage seals, rebuilt my original head and have it boxed up ready to go when needed.

BTW, the yong heng uses a one piece, second stage seal with an O ring under it. Luckily, I had installed similar seals before. install the 3 O rings on the piston. Then, put the seals in HOT water, let them get a little soft and pliable. Used a small set of needle nose pliers to stretch them just a tiny bit, enough that they would slip on the piston without any damage. If you're not careful, you'll ruin a seal before you get it on the piston. Go slow, don't force them on the piston.

Once the seals are on the piston, it does not want to go into the bore. I again heated the seals(and piston) in HOT water. Worked them a bit with my fingers to conform them to the piston. Then shocked them in ice water, letting them completely cool. Now, they JUST slipped into the head. Again, go slow, a little wiggling/working of the piston will get the seals in without damage.

The first stage rings are easy. just be careful you don't snap a ring as they are hard and brittle. I did break the used middle ring removing it from the piston...
Thanks.... that was all very helpfull! I was shocked when I took mine apart to inspect and discovered the high pressure rings were not split rings.  I was a little disappointed. At least with your help I see how to change them. This is one advantage I believe of the larger head tuxing unit. (Easy to change out the rings)I just ordered the tuxing from sbtech on aliexpress . The one that contains all the seperate lines of the yong heng within the head. I'm going to test it against the yong heng. If it works as good as the Yong heng it will win just by it's easy serviceability. I should have it by Monday, paid $340 for 110v  shipped.
Kris
Title: Re: Yong Heng Replacement Parts?
Post by: HighAltitudeAir on February 11, 2018, 02:20:41 PM
Any body know where to get a replacement auto stop gage for these chinese compresors?
Thanks
CH
Title: Re: Yong Heng Replacement Parts?
Post by: daveki on February 12, 2018, 03:25:06 PM
I ordered a Yong Heng compressor and will be using it to charge my Marauder, can someone tell me if the correct foster fitting will come with the compressor and if not what fitting do I need and the best place to get one?  I am a first time buyer/user of a PCP air rifle, don't have either my gun or compressor yet and would be nice when I do get them that I will have everything needed.

thanks,
dave
Title: Re: Yong Heng Replacement Parts?
Post by: Roger M on February 12, 2018, 05:58:50 PM
I am almost sure the part that you posted is for a tuxing compressor and I am almost sure again that the tuxing and Yong Heng parts are interchangeable. Go to pcp compressors the good the bad and the ugly there is a guy in that group that has a Yong Heng and the top end is all tuxing they say the tuxing is a better compressor
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on February 12, 2018, 10:32:09 PM
Is this what you are looking for?
https://www.aliexpress.com/item/Auto-stop-compressor-pressure-gauge/32812164010.html?spm=2114.10010108.1000013.6.4e47d4d1i7iIsu&traffic_analysisId=recommend_2088_3_90158_iswistore&scm=1007.13339.90158.0&pvid=6cc176d1-674a-4537-9e90-26dc3810ca06&tpp=1 (https://www.aliexpress.com/item/Auto-stop-compressor-pressure-gauge/32812164010.html?spm=2114.10010108.1000013.6.4e47d4d1i7iIsu&traffic_analysisId=recommend_2088_3_90158_iswistore&scm=1007.13339.90158.0&pvid=6cc176d1-674a-4537-9e90-26dc3810ca06&tpp=1)
Title: Re: Yong Heng Replacement Parts?
Post by: HighAltitudeAir on February 15, 2018, 11:30:40 AM
“Is this what you are looking for.”

Yep that is it. Thanks for the link. I searched Ali express for gages for over an hour and never seen this gage. I found gages for the tuxing compressor but not this one, or for the whole compressor.
Again thaks
CH
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on February 16, 2018, 02:13:32 AM
Great. Good luck. They are on New Year's break right now (it's actually today), so if you order it you probably won't see it ship for about 10 days.
Title: Re: Yong Heng Replacement Parts?
Post by: redtrucker610 on February 18, 2018, 06:38:36 AM
Its great to know parts are available for these little compressors. I have had mine now for almost a year. It's still pumping great but good to know parts are available. I think when my upper end gives out I would just replace the entire upper unit that is shown in this tread. Reading about the none split rings it seems it would be easier to just replace it as a unit.
Title: Re: Yong Heng Replacement Parts?
Post by: stony30 on February 25, 2018, 02:31:25 AM
I ordered a Yong Heng compressor and will be using it to charge my Marauder, can someone tell me if the correct foster fitting will come with the compressor and if not what fitting do I need and the best place to get one?  I am a first time buyer/user of a PCP air rifle, don't have either my gun or compressor yet and would be nice when I do get them that I will have everything needed.

thanks,
dave
Yes the compressor comes with a fill hose with the female foster fitting that will hook right up to your male fitting on your Marauder.
Title: Re: Yong Heng Replacement Parts?
Post by: BSJ on February 25, 2018, 10:52:50 AM
Anyone got a link to the sight window/fill gauge?

I went to use mine for the second time and found the tray I've got it in, wet with oil. I need to dig deeper, but I think the gauge is the source.

Thankfully, I store it on the fast food style serving tray or the oil would have leaked onto the carpet...
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on February 25, 2018, 03:52:16 PM
I haven't seen just the sight-fill gauge, but here is the front cover for the crank case. It's $20 + free s/h:

https://www.aliexpress.com/store/product/PCP-air-compressor-front-cover/2305020_32851043086.html?spm=2114.12010608.0.0.5e8cf45cl8uAbn (https://www.aliexpress.com/store/product/PCP-air-compressor-front-cover/2305020_32851043086.html?spm=2114.12010608.0.0.5e8cf45cl8uAbn)

Good luck!
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on February 25, 2018, 03:54:29 PM
Just another quick note... that happened to me once (twice) when I had removed the front cover and managed to pinch the rubber gasket behind it underneath one of the screws. If you've removed the front cover, just maybe double check that you didn't pinch the edge of the gasket underneath one of the 4 screws.
Title: Re: Yong Heng Replacement Parts?
Post by: BSJ on February 25, 2018, 07:16:33 PM
Thanks!

It is the gauge. Actually the window itself.

A drip forms at the inside edge of the outer metal ring. Not on the threaded part that screws into the cover.
Title: Re: Yong Heng Replacement Parts?
Post by: AncientSword on March 18, 2018, 12:57:13 AM
Just another quick note... that happened to me once (twice) when I had removed the front cover and managed to pinch the rubber gasket behind it underneath one of the screws. If you've removed the front cover, just maybe double check that you didn't pinch the edge of the gasket underneath one of the 4 screws.

I just re-built the top end on my Yong Heng last night.  I put it back together and everything is working, but I am leaking oil around the case cover.  I can't seem to get that rubber cover to seat.  It seems like it has shrunk, as I can get it into two of the corners, but it always pulls off the other two.  Did you experience anything like that? I am wondering if I need to order a new one?
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on March 18, 2018, 01:45:57 PM
That rubber cover gasket is finicky. Wish I had a better suggestion than just to gradually seat it into place. I've had to try a couple of times to get it not to leak. I think the last time I put all four screws n loosely then tried to get the bottom two tighter first. I was sure I needed a new cover gasket but it eventually went into place and sealed up fine.
Title: Re: Yong Heng Replacement Parts?
Post by: bandg on March 18, 2018, 01:57:47 PM
I've only taken the front cover off for initial clean out but have not had any leaks.  If it is a major problem, you might consider gasket adhesive to secure the gasket to the cover.  If I recall, there is a slot that the gasket fits into in the cover and it could be placed in there with the sticky gasket adhesive available in any auto parts store.
Title: Re: Yong Heng Replacement Parts?
Post by: AncientSword on March 18, 2018, 07:51:03 PM
I used gasket maker and it sealed,  but I think the rubber gasket is needed,  as I am getting a ton of oil out of the breather now.  It may be that the gasket dampens things in there,  because I wasn't getting that before.
Title: Re: Yong Heng Replacement Parts?
Post by: bandg on March 18, 2018, 08:13:13 PM
I really intended to convey that gasket adhesive could be used to locate the stock gasket in the slot for accurate placement but gasket maker should work as well.  I don't see how use of such gasket maker could cause anything other than a leak at the gasket surface but who knows.
Title: Re: Yong Heng Replacement Parts?
Post by: AncientSword on March 18, 2018, 09:42:03 PM
It isn't leaking around the gasket at all, but I am getting oil "spit" out of the breather on a constant basis.  It spits it out all over the place in little droplets.  The oil level went down about 15% in the window within like 15 minutes of run time. I was checking for leaks, but don't see any except the spitting from the breather.

I put a brand new head on it, with new piston and crank.  Everything on the top side is new, with about an hour run time.  I ran it with no load for two cycles of about 10 minutes to break things in. It is building pressure fine, but without the gasket in, it seems to make more noise as well as the spitting.  It makes me nervous listening to it this way versus how it originally sounded.  I am trying to order a new gasket, but I can only find the new front cover that includes the gasket.  I emailed the guy I bought it from to see if I can just buy a new gasket.  I tried like 20 times to get the gasket to fit in the grooves. My uncle came over and tried it.  It basically shrunk and will not fit. There is at least a 1/16" gap from top to bottom if it is in the grooves on one or the other.

For anyone that is interested in why, I rebuilt it because it was struggling to compress anything above 3000 psi any longer.  I believe that I messed it up, trying to compress helium.  I plumbed helium into the intake and tried to compress it.  I had to turn the pressure up to about 20 psi on the helium regulator to get the compressor to work with helium.  It did work and I compressed 2000 psi into an SCBA bottle.  The problem is that it wastes a lot of helium doing it this way.  I also believe that I put too much stress on it and although my temp. never got above 60 C, my cylinder showed signs of overheating towards the top. There was also a lot of evidence of things starting to come apart. Lots of grey matter was in the oil and case.  I really think that this piston could benefit from a bushing.  The pin was super sloppy and there was lots of movement going on where it shouldn't as well. I had 26 hours of run time on it when I took it apart.

 
Title: Re: Yong Heng Replacement Parts?
Post by: kingrude1 on March 18, 2018, 10:48:58 PM
It isn't leaking around the gasket at all, but I am getting oil "spit" out of the breather on a constant basis.  It spits it out all over the place in little droplets.  The oil level went down about 15% in the window within like 15 minutes of run time. I was checking for leaks, but don't see any except the spitting from the breather.

I put a brand new head on it, with new piston and crank.  Everything on the top side is new, with about an hour run time.  I ran it with no load for two cycles of about 10 minutes to break things in. It is building pressure fine, but without the gasket in, it seems to make more noise as well as the spitting.  It makes me nervous listening to it this way versus how it originally sounded.  I am trying to order a new gasket, but I can only find the new front cover that includes the gasket.  I emailed the guy I bought it from to see if I can just buy a new gasket.  I tried like 20 times to get the gasket to fit in the grooves. My uncle came over and tried it.  It basically shrunk and will not fit. There is at least a 1/16" gap from top to bottom if it is in the grooves on one or the other.

For anyone that is interested in why, I rebuilt it because it was struggling to compress anything above 3000 psi any longer.  I believe that I messed it up, trying to compress helium.  I plumbed helium into the intake and tried to compress it.  I had to turn the pressure up to about 20 psi on the helium regulator to get the compressor to work with helium.  It did work and I compressed 2000 psi into an SCBA bottle.  The problem is that it wastes a lot of helium doing it this way.  I also believe that I put too much stress on it and although my temp. never got above 60 C, my cylinder showed signs of overheating towards the top. There was also a lot of evidence of things starting to come apart. Lots of grey matter was in the oil and case.  I really think that this piston could benefit from a bushing.  The pin was super sloppy and there was lots of movement going on where it shouldn't as well. I had 26 hours of run time on it when I took it apart.

 
Just sitting and thinking about your problem, wouldn't it spitting oil out the filler be a sign of pressure getting into bottom of the compressor? Would seem to me that would be the only thing that would cause the oil to spit out with pressure. Maybe a leak between the new head and block letting pressure into the block, maybe faulty gasket? Or faulty rings on pistons? Good luck.
Title: Re: Yong Heng Replacement Parts?
Post by: bandg on March 18, 2018, 10:50:33 PM
Still can't understand how the gasket (or cover seal) could do anything beyond physically leak.  It seems like you have a "blow-by" problem where the high pressure air in the upper cylinder(s) is leaking past the piston and is pressuring the crankcase.  I believe there has been one case of the cover reported to have "exploded" so I would be certain this is not happening before running it too much.

As he just said, beat me to it.
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on March 18, 2018, 11:30:20 PM
I like kingrude1's explanation - the only way to spit oil out the breather is to have it pressurized. As he said, maybe you are getting blowby past the rings on the piston. Another less likely cause could be if the one-way valve on the inlet to the 2nd stage is partially plugged or otherwise restricting the flow which would also build up back pressure in the 1st stage. But kingrude1's explanation seems more likely.
Title: Re: Yong Heng Replacement Parts?
Post by: AncientSword on March 18, 2018, 11:49:02 PM
I understand what you are saying,  but I wasn't getting any of that oil out the vent before I removed the gasket.

There must be some blow back going on,  not debating that.

I didn't assemble the top end,  it was shipped to me.  I just removed the old cylinder and disconnected the old piston,  then installed the new one. I can't be sure how well the work was done without taking it all apart.  It should be right though as it came from the factory,  but we are talking about the Yong heng  factory here.

Title: Re: Yong Heng Replacement Parts?
Post by: dlee on March 19, 2018, 01:18:27 AM
Hmm, okay let's assume the cover gasket must somehow be involved. What if, and I am just speculating wildly here, the gasket was seated almost but not quite right so that when the piston was on it's upstroke it was able to draw air in through the leaky seal. Then on it's downstroke because of the design of the gasket, the additional pressure sealed the leak leaving the oil nowhere to go but up through the breather. Since the upstroke is the exhaust stroke, you'd still be able to compress air. This might also explain why you have trouble at high pressure. I dunno, that's a bit out there, but I suppose something weird like that is possible.
Title: Re: Yong Heng Replacement Parts?
Post by: bandg on March 19, 2018, 12:01:30 PM
David, that is a stretch but I suppose it is possible.  In any event, it certainly seems to be a pressure in the crankcase problem that should be corrected before further use.  Easy enough to take the cover off and look for an issue such as David is mentioning. 
Title: Re: Yong Heng Replacement Parts?
Post by: Tweeter on March 19, 2018, 12:24:13 PM
Could grab a new cover.


https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1 (https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1)
Title: Re: Yong Heng Replacement Parts?
Post by: Tweeter on March 19, 2018, 12:28:24 PM
What kind of oil are you using.  If it isn't a non-detergent oil it may be foaming so much that it reaches the breather?  Odd that just taking off the front cover could cause it...
Title: Re: Yong Heng Replacement Parts?
Post by: BSJ on March 19, 2018, 01:38:31 PM
Could grab a new cover.


https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1 (https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1)

I just received one of these covers to replace mine that has a leaky gauge. Came with a new gasket and screws.

I haven't installed it yet...
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on March 19, 2018, 02:01:43 PM
I also like checking on the foaming of the oil. Simple to check - I'd really eliminate the simpler ideas before going for something like the somewhat wacky one I postulated. That was just an off-the-cuff attempt to explain why the gasket was involved. Not my favorite explanation at all.
Title: Re: Yong Heng Replacement Parts?
Post by: AncientSword on March 19, 2018, 02:22:20 PM
What kind of oil are you using.  If it isn't a non-detergent oil it may be foaming so much that it reaches the breather?  Odd that just taking off the front cover could cause it...

I'm running Mobile DTE Iso46 in it.
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on March 19, 2018, 04:02:03 PM
from the Mobil website:
Mobil DTE™ Oil Named Series 

Premium Performance Circulating Lubricants

Product Description
The Mobil DTE™  Oil Named Series of lubricants are premium performance circulating lubricants designed for applications including steam and hydro turbine sets and other systems where long lubricant service life is required. Mobil DTE Oil Named Series lubricants are formulated from highly refined base stocks and an additive system which provide an extremely high level of chemical and thermal stability, rapid and complete separation from water and a high resistance to emulsification. They provide excellent protection against rust and corrosion, including resistance to salt water, and good antiwear properties. They have a high viscosity index which ensures minimum variation of film thickness with temperature and minimum power loss during the warm up period. These grades have excellent air release properties which allow entrained air to separate, thus avoiding pump cavitation and erratic operation.

So I'm guessing it isn't foaming of the oil.
Title: Re: Yong Heng Replacement Parts?
Post by: be4meliz on May 11, 2018, 11:20:43 AM
I have a Vevor(I believe) "yong Heng knockoff" & am looking for 2nd stage seals. Instead of rings, it has a delron cup that screws into piston rod. Any help, as the companies that sell these(out of Cali.) do not seem to know where to obtain.
Title: Re: Yong Heng Replacement Parts?
Post by: BSJ on May 11, 2018, 11:46:13 AM
Could grab a new cover.


https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1 (https://www.aliexpress.com/item/PCP-air-compressor-front-cover/32851043086.html?spm=2114.10010108.1000014.7.3d447c8cW2Ktj6&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.98466.000000000000000&pvid=6873dc2d-c4c0-49fa-9d6f-def6ad2855af&tpp=1)

I just received one of these covers to replace mine that has a leaky gauge. Came with a new gasket and screws.

I haven't installed it yet...

Forgot to report that the cover and gasket went on without a hitch. I reused the old gasket, as it only had an hour of use one it. No leaking anywhere, so far.
Title: Re: Yong Heng Replacement Parts?
Post by: HuskyDude on May 11, 2018, 01:29:53 PM
Just another source to look for parts.

PCPMart (https://www.pcpmart.com/)
Title: Re: Yong Heng Replacement Parts?
Post by: hollowpoint1911 on May 13, 2018, 07:25:52 AM
I have a Vevor(I believe) "yong Heng knockoff" & am looking for 2nd stage seals. Instead of rings, it has a delron cup that screws into piston rod. Any help, as the companies that sell these(out of Cali.) do not seem to know where to obtain.

I had to order parts from AliExpress (China) to get parts for these compressors. eBay doesn't have much at all. What you have to do is fine a seller who carries the same model compressor as you do, and then ask to buy whatever part you need. Make sure you can provide them with a clear picture of what you want, so there's no confusion. The search engine on AliExpress is total trash, so it's just easier to reach out and ask.

If you send me a picture of the part you need, I'll keep an eye out on AliExpress, and I'll check my parts stash to see if I have it. I just swapped the Vevor head with one from a Yong Heng. I'm not looking to part everything out since I want to keep it for backup/comparison, but I do have some extra parts.
Title: Re: Yong Heng Replacement Parts?
Post by: be4meliz on May 23, 2018, 09:38:51 AM
Picture is blurry- roughly 3/8" delron cup that screws into top of 2nd stage piston(cone shaped) Will try to get better shot with my camera.
Title: Re: Yong Heng Replacement Parts?
Post by: Mondo on June 08, 2018, 03:15:55 AM
Yep,

That's a complete head. first stage piston, rings, second stage piston/seals, the whole top end. Simply remove the end of the stainless lines that connect to the compressor and the two bolts that attach the first stage head, slip the whole head off. It does help if the crank shaft is at the top of its stroke when removing the lower connecting rod end.

The new head, even included the paper gasket.

I changed the head on mine because I was worried about oil blow by on the first stage piston rings. I had about 10 hours of run on it. its wasn't really bad, just bad enough to worry me. The complete, new head went on without issue. I seated the rings for about 10 minutes at zero load. changed the oil. I have about 3 hours on the new head, very little, what I would consider a normal amount of oil blow by still.

I took a set of first stage piston rings and second stage seals, rebuilt my original head and have it boxed up ready to go when needed.

BTW, the yong heng uses a one piece, second stage seal with an O ring under it. Luckily, I had installed similar seals before. install the 3 O rings on the piston. Then, put the seals in HOT water, let them get a little soft and pliable. Used a small set of needle nose pliers to stretch them just a tiny bit, enough that they would slip on the piston without any damage. If you're not careful, you'll ruin a seal before you get it on the piston. Go slow, don't force them on the piston.

Once the seals are on the piston, it does not want to go into the bore. I again heated the seals(and piston) in HOT water. Worked them a bit with my fingers to conform them to the piston. Then shocked them in ice water, letting them completely cool. Now, they JUST slipped into the head. Again, go slow, a little wiggling/working of the piston will get the seals in without damage.

The first stage rings are easy. just be careful you don't snap a ring as they are hard and brittle. I did break the used middle ring removing it from the piston...

The seals are a non split type, but there is no need to do the above process, that is because the second stage seal head screws off to replace the seals.
I suspect this might be the cause of a failure in some pumps as the seal head comes loose and screws out hitting the head.
Title: Re: Yong Heng Replacement Parts?
Post by: jab on June 08, 2018, 05:09:30 PM
Does  anyone know  what the torque is  on these  bolts/cap screws ?  we came up with  40 lbs.  by checking the torque  to break them loose.  This pump we are still testing out.  has not been ran under  a load
Title: Re: Yong Heng Replacement Parts?
Post by: hunter457 on June 28, 2018, 07:29:25 PM
 8) seeking stator windings
Title: Re: Yong Heng Replacement Parts?
Post by: sykocis on July 23, 2018, 10:16:03 PM
Does anyone have a guess as to what part would be needed to repair the mophorn compressor with a crankcase cover that exploded? 
Title: Re: Yong Heng Replacement Parts?
Post by: Harpoon1 on July 24, 2018, 01:21:14 PM
Does anyone have a guess as to what part would be needed to repair the mophorn compressor with a crankcase cover that exploded?

Wow!

Tell us more.....when.....how....what psi.......please!
Title: Re: Yong Heng Replacement Parts?
Post by: cosmic on July 24, 2018, 01:53:19 PM
https://www.aliexpress.com/item/4500PSI-PCP-compressor-spare-parts-compressor-crankcase-whole-set-1-piece-lot/32833569065.html?spm=2114.search0104.3.8.61d1e848h4G7Kd&ws_ab_test=searchweb0_0,searchweb201602_4_10152_10151_10065_10344_10130_10068_10324_10547_10342_10325_10546_10343_10340_10548_10341_10545_10696_10084_10083_10618_10307_10869_10868_10059_100031_10103_10624_10623_10622_10621_10620,searchweb201603_16,ppcSwitch_5&algo_expid=569ad511-d245-45b3-a2a6-f0a841dc865e-1&algo_pvid=569ad511-d245-45b3-a2a6-f0a841dc865e&priceBeautifyAB=0 (https://www.aliexpress.com/item/4500PSI-PCP-compressor-spare-parts-compressor-crankcase-whole-set-1-piece-lot/32833569065.html?spm=2114.search0104.3.8.61d1e848h4G7Kd&ws_ab_test=searchweb0_0,searchweb201602_4_10152_10151_10065_10344_10130_10068_10324_10547_10342_10325_10546_10343_10340_10548_10341_10545_10696_10084_10083_10618_10307_10869_10868_10059_100031_10103_10624_10623_10622_10621_10620,searchweb201603_16,ppcSwitch_5&algo_expid=569ad511-d245-45b3-a2a6-f0a841dc865e-1&algo_pvid=569ad511-d245-45b3-a2a6-f0a841dc865e&priceBeautifyAB=0)
Title: Re: Yong Heng Replacement Parts?
Post by: cosmic on July 24, 2018, 01:57:12 PM
looks likely dropped on front of it.. no real pressure in crankcase.. the oil breather would go first.. check piston for holes or cracks...
Title: Re: Yong Heng Replacement Parts?
Post by: cosmic on July 24, 2018, 02:02:00 PM
cover only
https://www.aliexpress.com/item/PCP-single-cylinder-air-compressor-front-cover/32851043086.html (https://www.aliexpress.com/item/PCP-single-cylinder-air-compressor-front-cover/32851043086.html)
Title: Re: Yong Heng Replacement Parts?
Post by: sykocis on July 24, 2018, 04:49:35 PM
Was filling the cylinder for my Bullboss.  It stopped filling at 40 Bar.  Then - BOOM!!!  Found part of the case cover lodged in my garage door.  Found the breather in-between the radiator and bumper of my SUV.  I'm not really sure what happened.  Some fluke accident.  Maybe a clogged breather.  Maybe a seal failed and there was back-pressure going back in to the crankcase.  I'm just happy to be uninjured, seeing as how that piece of metal that was lodged in the garage door came flying by, fairly close to my head.  I'll need to pull the compressor down and inspect it to find the failure.   Anyway, thank you guys for the links.
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on July 24, 2018, 09:42:04 PM
40 bar is only 580 psi. IMO, that wouldn't be enough to blow out the crank case which normally operates between atmospheric and 150-200 psi. I've had mine up as high as 350 psi when trying out the booster pump concept (yeah, don't run it that high). There must have been a defect in it or the screws failed or something (maybe the threads were improperly tapped?). The breather is plastic so its threads would give way at a pressure far below what was needed to blow up the crankcase (again, unless it was somehow defective). And I gotta believe the same goes for back-pressure going into the crankcase - it would blow out the plastic breather by design.

Must have been an amazingly scary moment - glad you're okay.
Title: Re: Yong Heng Replacement Parts?
Post by: dlee on July 24, 2018, 09:44:10 PM
just looke more closely are your (frightening) photo. I'm guessing a casting defect? The screws did not fail since they are still there holding what's left of the crankcase. And the breather did not blow out either. Yowza.
Title: Re: Yong Heng Replacement Parts?
Post by: sykocis on July 24, 2018, 09:59:09 PM
I put the breather back in after I found it.  That’s why it was in the picture.  Like I said before,  I’m chalking it up to freak accident that probably I would never happen again.  Definitely once in a lifetime lol.  I’d guess casting defect.  I’m debating on if I want to rebuild it or, if I should save some pennies and get a more expensive and well made pump.  I’m confident if I rebuilt the thing, it would work without issue but, understandably, I’m a bit shaken.  Regardless,  I made it out with ten fingers and, ten toes.  My hand pump came in today and my cylinder pumped up.  It’s time again to put pellets to paper my friends.  Thank you all for the advice and the concern.  That’s why I have come to love the community here.
Title: Re: Yong Heng Replacement Parts?
Post by: sykocis on September 07, 2018, 10:11:03 PM
Back again after some time.  So, the replacement parts for the comprebfinally arrived from China today.  I ordered the parts over a month ago.  Oh well.  So I start the process of tearing down the compressor.  I begin unscrewing the tube fittings on the left hand side of the compressor (brass block, don’t know what it’s called).  I noticed a brass part with threads laying in it loose.  I dump it out and it looks like some type of filter.  Regardless, I came loose, probably due to vibration.  I also notice some case screws laying under the motor.  So I start blowing air in the top of the brass block on the right hand side of the compressor with my mouth.  No air comes out the outlet side.  I’m working on pulling it apart now.  Maybe there was more to the front casing exploding than I first thought.  I’ve heard that you should pull them down once you receive them from wherever you order them from, and check everything.  That was my mistake.  I jumped the gun and just for it.  I’ve learned my lesson.  Hopefully, I can get her operating without issue.  Fingers crossed.
Title: Re: Yong Heng Replacement Parts?
Post by: Csexton on October 14, 2018, 09:14:52 PM
I ordered many parts from AliExpress. It took about 2 weeks to arrive.
Title: Re: Yong Heng Replacement Parts?
Post by: hunter457 on October 16, 2018, 01:20:34 PM
I just bought another new compressor, plenty of spare parts now lol
Title: Re: Yong Heng Replacement Parts?
Post by: Rat Sniper (AKA: PaulT58) on October 16, 2018, 03:17:29 PM
If anyone else is interested, I found this digital thermometer on Amazon for $6.99.  It displays Fahrenheit instead of Celsius.  The specs say it will read from -58F to 199F.   The max operating temp of the YH is 65C which converts to 149F, so this should work...  It is the same size as the digital thermometer that comes with the YH Compressor.

https://www.amazon.com/gp/product/B073RP1476/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1 (https://www.amazon.com/gp/product/B073RP1476/ref=oh_aui_detailpage_o04_s00?ie=UTF8&psc=1)

Title: Re: Yong Heng Replacement Parts?
Post by: Voltar1 on October 22, 2018, 02:08:04 PM
For the lad with oil coming out breather. These compressors are splash lubricated and to prevent oil getting to the breather the rubber cover gasket is also a 'dam' to keep the violently splashing oil going where it shouldnt. Do not remove that rubber gasket.
If you need to add some sealant use a smear of Loctite gasket maker or equivalent.
Title: Re: Yong Heng Replacement Parts?
Post by: Voltar1 on October 25, 2018, 10:12:19 PM
just looke more closely are your (frightening) photo. I'm guessing a casting defect? The screws did not fail since they are still there holding what's left of the crankcase. And the breather did not blow out either. Yowza.
Curious where you get your information wrt the case seeing anywhere close to 100psi? 580psi on that case? Darwin award that is. Casting defect? Designed for atmospheric and blows out at likely 100s psi above that and that os a casting defect? Sorry man but bad info you be giving folks.