Tweeter, I JUST finished converting my Vevor compressor with the Yong Heng head over the weekend. I haven't had the time yet to fill up a tank, but on quick initial test, everything works. You're correct, the bottom end (crankcase and mounting points) are the exact same on the Vevor and Yong Heng. It cost me $150 for all the conversion pieces.I've been meaning to write up a post on my experiences, but life keeps getting in the way. When I got my Vevor, I had oil coming out of every fitting, hose, etc, and I did a full tear down before running it. What I found wasn't pretty...the metal castings are really rough with tons of slag left on it. The mfg then paints over the slag with silver paint, assembles the compressor and runs the compressor to "break it in". My compressor had metal shavings/slag everywhere...all the way up to the second stage. Just doing oil changes won't get all the crud out, you have to go through piece by piece to clean things out. There is a rubber screen/gasket thats right behind the crankcase cover, and it will prevent metal shavings from draining out with the oil when you do a oil change. The metal shavings like to get stuck to the rubber screen and stay inside the machine instead of getting drained out.My recommendation to you is to tear it all down, and clean it out. In my case, I had metal debris sitting in the crank, piston ringlands, and second stage compression orings. If I had to take a guess, I'd say that you probably have a damaged oring in the second stage. If that's the case, it's a easy fix and I think they included some spare orings with the Vevor originally. Finding parts for these compressors is an adventure. The search engine on AliExpress is garbage (and parts aren't sold on ebay). The most effective method I've found is to have a picture of whatever part you need, and then message sellers on AliExpress asking them if they can sell the part. You might get lucky and they'll already have a product link to send you, or (like in my case) you'll have to wait for them to create a new item listing so you can purchase it. If you can identify the parts you need, I might be able to help you source them as well.
I have this exact same compressor. Keeping my fingers crossed, only used it once so far to top of my 30 min CF tank from approx 2500psi to 4500psi. It worked perfectly.
have you checked for leaks or slow leaks,, ?
Hey Justin,Sorry, brain fart on my part, if I would have taken 2 minutes to go look at the Vevor piston assembly I have, I would have known the 2nd stage seal wasn't just a normal oring.Anyway, once you figure out which part failed, I would suggest contacting "Joto Valve and Pump Store" on AliExpress. They sell the "Vevor style" cylinder head, so there shouldn't be a problem getting other replacement parts (aside from the slow shipping from China).Here's a link to a listing from Joto where they sell the cylinder head. Just use the page to contact them and ask for whatever it is you need. http://s.aliexpress.com/RjuUjuQ7
Hey Andy, is that Vevor piston you have in good shape or did yours stop working also and thats why you switched to yong heng parts?
Justin,I have ran my Vevor for approximately 17 mins total (1 run) and my oil turned dark. I changed the oil in it already and left it ready to use it again for when the time comes that I need to top off my tank again. More than likely that could be weeks before I actually use it again. Not that much shooting lately as I'd like.Anyways, looking at your picture of the 2nd stage ring, to me it looks fine, am I missing something?
If the second stage rings ate a problem, you might be able to drop in a tuxing piston assy with the split rings. I have a spare one if you want to try it. I also have a tuxing top end as well.
Quote from: WiseGuy on May 15, 2018, 10:57:55 AMJustin,I have ran my Vevor for approximately 17 mins total (1 run) and my oil turned dark. I changed the oil in it already and left it ready to use it again for when the time comes that I need to top off my tank again. More than likely that could be weeks before I actually use it again. Not that much shooting lately as I'd like.Anyways, looking at your picture of the 2nd stage ring, to me it looks fine, am I missing something?Jimmy, that picture is from when my compressor was brand new. I had to tear it down when I got it because it had been shipped upside down with a bit of oil in it so the head (above the piston) was full of oil. I plan to take it apart this afternoon and I bet it doesn't look that good anymore!