Yong Heng compressor ... I just bought 1 ...

[KnifeMaker]

IMHO, people are stressing too much on something undeserving such concern. It's a basic tool, not an heirloom. A hammer, not a fine micrometer. Used within the scope of its design and attention to its basic needs, the difference between when it finally fails under those conditions and one micro-managed by a team of fanatics won't amount to a hill of beans when the bottom line is tallied.

If one's nature has equipped them with upper level guns, with a commensurate attention to their futures, a YH won't be the HPA accessory of choice. It'll be one deserving of that owner's meticulous care.

But for me with my entry level Synrod, the YH has been an excellent choice. I did my research for months before I began and have realistic expectations for my situation. I've met and exceeded them. And while all is ducky as I fill out my first year on the Darkside the inevitable is being prepared for in the interim.

I'm not using super whompadyne oil in my YH, but it's far better than what was recommended when I got it. Other than the first fill that I replaced after the first month, all subsequent use, i.e., refilling my gun one to six times a day for the past six months, the fluid's level and opacity has never varied. It's still a pleasant transparent red like it began. I've never had a smell. There is no oil in my filters. The sound never changes, the fills are consistent, smooth, and reliably accurate... taking less than a minute for a 19-3.3k fill. My HPA tool is working fine and there is no indication that's going to change. But it will: Stuff happens.

When it does happen to fail I won't blame it on my compressor oil choice... even though it's not on anyone's list heretofore mentioned, but mine. Ya do your best and take what you get. Then move on. Spend your stress allotment on the realities of your life, not your imagination's.

The higher quality oils are NOT to make the unit live longer but rather to keep varnish off the reed valves. You only fill your gun. You are not using the compressor long enough, Hard enough,  to be able to judge anything. Fill tanks and the relists will change quickly!


There are very good reasons this topic has been ongoing for years here. Experience!


Knife

[WI_Hedgehog]

I give up. At least Dan and Cooter paid attention. LOL


What is the old saying, "You can beat a dead horse near the water, but you can't make him think."

Most of the oils here are for lower pressure compressors. There has been and is an entire industry built around HP compressors. How can any one not understand this. they are universes apart.


Would you put a porcupine in a clown's balloon bag? Use a dove egg in a Slingshot? (Well, maybe you would do that...) Anyway, use a product made for the high stresses of a HP compressor. I don't know what else to say.


[totally misquoted from] Knife

I bought scuba compressor oil because of you guys, thank you!

[Mr Fluffy Tail]

and any tricks to making them last longer would be appreciated

 thanks ...DH...

.. just getting in to more advanced equipment myself so i can give a few personal mental notes on the hung long .. first its not a high end compressor and 'oil' isnt going to save it, extend its life or nothing of the sort, yeah use a good oil and change it occasionally, thats 'basic' and understood, so is keeping it cool enough, use a dam fan to lol .. the pump is designed to be an alternative to 'you' going to the shop to refill your tank(s) $-wise, so likely you wont save any money with this pump before it breaks but you will be capable to fill your tanks at home for the same money until it does ... the exceptions now .. in my own opinion researching and looking at it -

the 'real' enemy of the pump is condensation and moisture left in the parts after use .. if you are mechanically inclined enough to be able to disassemble things and reassemble without damaging anything you can likely prolong its life quite a bit past its designed 'die rate' ... the cylinder and piston itself i dont think needs to be disassembled ,but EVERY manifold, line, fitting, check valve, and related oring needs to be cleaned, dried and treated after EVERY days use or before storage more than a day lets put it that way ... also the water jacket needs to be sprayed out with a protectant like they make for pressure washer pumps ... do that, and it should last a long time trouble free .. the way i have it figured 15 minutes to partially break things down and do all that 'after' the initial figuring it out and learning things .. so, maybe not a 'trick' . but the 'hard skinny' lol .. like i said, use it like you stole it and you'll likely get your moneys worth anyway ..

[tracker1955]

The best advice I can give besides using good oil is to open both bleed valves after use to clear any water from the hurricane separators, and to remove the tampon filter from the black filter housing so the line and fittings dry. The tampon filter will air dry and can be used multiple times before enough oil residue shows up on it to warrant throwing it away. I also don't run fresh tap water through the pump to the water jacket in an attempt to prevent hard water scale from forming inside the water jacket. I have a sealed container of water I use that has a bottle of water wetter added to it to aid in cooling and prevent scale formation. My three-year-old unit paid for itself in the first year so I guess that would make the last two years free, and still running strong, and filling mostly my 45 min scba tank.

If I were still going to the dive shop for fills it would require a 50 mile round trip to Nashville, plus the cost of fills that were $10 each the last I knew and it may be more now. There was only one shop in town capable of filling to 4500 and if their tank didn't have enough air in for a full fill you had to either leave your tank or get what pressure they had available. 

[Keithy]

I like to take tubing off and blow(home compressor,120 psi) air directly into the brass fittings in the head. When the water vapor quits coming out,(8 to 10 times each ) I blow as best I can through the bleeders(screws removed) though the filler line and filter housing. I leave the filter and bleed screws and tubing off until I'm ready to use it again. It dosent take as long to do it as does to type it.

[fotomat1]

Having worked in Advertising for 40 years I would be willing to bet that mention of Mobil as the lubricant of choice in the booklet is a Paid Placement. Every major oil company has an almost exact duplicate as far as specs regarding that product. Mention of a specific brand does pay dividends both by being printed then by word of mouth. You would be surprised how many paid placements you experience in life....from a certain soft drink in a movie to a coffee cup on a talk show host desk. Just use a top grade lubricant,,,don't run it till it blows up,,,change it often.

[Randy00]

Mine just seized up after 10 minutes of use yesterday. Only thing I have done differently is I switched from RP to Chemlube.. .. Probably has nothing to do with it. I had about 18 hours on it using RP and under 1 hour with chemlube and when I had it open to replace the gaskets a while back it was in pristine condition with the Rp. It had about 10 hours on it after I replaced the gaskets with RP.  I'll crack it open again and see what happened. But I'm sure it's just a coincidence that I just switched over to the better lube less than an hour before it died..   

[OleTomCat]

What locked up?  Where's the point of failure?  Pictures?

Mine just seized up after 10 minutes of use yesterday. Only thing I have done differently is I switched from RP to Chemlube.. .. Probably has nothing to do with it. I had about 18 hours on it using RP and under 1 hour with chemlube and when I had it open to replace the gaskets a while back it was in pristine condition with the Rp. It had about 10 hours on it after I replaced the gaskets with RP.  I'll crack it open again and see what happened. But I'm sure it's just a coincidence that I just switched over to the better lube less than an hour before it died..   

[Randy00]

What locked up?  Where's the point of failure?  Pictures?

Mine just seized up after 10 minutes of use yesterday. Only thing I have done differently is I switched from RP to Chemlube.. .. Probably has nothing to do with it. I had about 18 hours on it using RP and under 1 hour with chemlube and when I had it open to replace the gaskets a while back it was in pristine condition with the Rp. It had about 10 hours on it after I replaced the gaskets with RP.  I'll crack it open again and see what happened. But I'm sure it's just a coincidence that I just switched over to the better lube less than an hour before it died..   

I said "I'll crack it open" ..that's a future tense statement.

Here it is.. More carbon than I have ever seen. Top of the piston sheered off and the cylinder walls are ruined. This is after less that an hour using it. So.. back to Royal Purple for me if I decide to rebuild this thing.

[Airnut]

Randy
Sorry for your bad luck.
You are case in point why there is so many different options on what is the best oil to use.
It dont really seam to matter what you run.
You either get a good one or a bad one.

[Randy00]

Randy
Sorry for your bad luck.
You are case in point why there is so many different options on what is the best oil to use.
It dont really seam to matter what you run.
You either get a good one or a bad one.

This was one of the good ones I guess.. so many hours with Royal Purple then I put the other stuff in and..ruined..

[tracker1955]

Easy fix if cylinder walls damaged.
https://www.aliexpress.com/item/32826327223.html?spm=a2g0o.productlist.0.0.113b5491nZ7AQI&algo_pvid=ccf53a68-ba29-43ca-9953-e73f428355c3&algo_expid=ccf53a68-ba29-43ca-9953-e73f428355c3-0&btsid=ea259485-c872-477a-8055-dee880e8e9bf&ws_ab_test=searchweb0_0,searchweb201602_5,searchweb201603_60

[OleTomCat]

The brass should not have scored the cylinder walls, they are steel.  All you should need is one of these.

https://www.aliexpress.com/item/4000619417179.html?spm=a2g0o.cart.0.0.28d33c0015Lt3y&mp=1

[Randy00]

It's scored alright.. The ring also came off. It was stuck when I pulled the head off.
Also the piston/s might work but the cylinder head is different as mine is a DAVV scu30 without the water collection block.

[tracker1955]

If you change only the second stage piston/seals keep in mind you'll have to remove the snap rings on the wrist pin and remove it to access the head of the socket head cap screw below. I found no way to get an allen wrench under the wrist pin.

 At $60 for the whole top end, it's still way less than the cost of a new compressor.

[Dan H]

Mine just seized up after 10 minutes of use yesterday. Only thing I have done differently is I switched from RP to Chemlube.. .. Probably has nothing to do with it. I had about 18 hours on it using RP and under 1 hour with chemlube and when I had it open to replace the gaskets a while back it was in pristine condition with the Rp. It had about 10 hours on it after I replaced the gaskets with RP.  I'll crack it open again and see what happened. But I'm sure it's just a coincidence that I just switched over to the better lube less than an hour before it died..   

If you got Chemlube 751 or Nuvair 751 you know it was not the oil , that is a fact .... we have to many running it now that are showing a big improvement over royal purple and the like .... like so many other's the damage was more than likely helped/caused  by royal purple since it is not designed to run in this application .... put the new parts in it , and then start running the 751 is what I would do then you start off new not dieseling up the second stage ...

[tracker1955]

One other thing came to mind related to my earlier post and that's heat buildup, if your temperature gauge wasn't reading right, or you forgot to monitor it and it got overly hot, or your water pump wasn't pumping correctly, these could all lead to a failure even with the better oil.

[Randy00]

Mine just seized up after 10 minutes of use yesterday. Only thing I have done differently is I switched from RP to Chemlube.. .. Probably has nothing to do with it. I had about 18 hours on it using RP and under 1 hour with chemlube and when I had it open to replace the gaskets a while back it was in pristine condition with the Rp. It had about 10 hours on it after I replaced the gaskets with RP.  I'll crack it open again and see what happened. But I'm sure it's just a coincidence that I just switched over to the better lube less than an hour before it died..   

If you got Chemlube 751 or Nuvair 751 you know it was not the oil , that is a fact .... we have to many running it now that are showing a big improvement over royal purple and the like .... like so many other's the damage was more than likely helped/caused  by royal purple since it is not designed to run in this application .... put the new parts in it , and then start running the 751 is what I would do then you start off new not dieseling up the second stage ...

If you read the first part, you saw that I had it apart using the RP to put a gasket in and found no problems at all after many hours of use. It was only after putting the 751 for less than an hour that this happened.

[tracker1955]

Sorry, just reread some of the posts, saw you said yours was a Davv not Yong Heng. I keep a list of parts for the YH saved on my computer, but not for Davv.

[Randy00]

Sorry, just reread some of the posts, saw you said yours was a Davv not Yong Heng. I keep a list of parts for the YH saved on my computer, but not for Davv.

everything looks pretty similar, and likely interchangeable. The only thing I don't know is if the hp piston is the same length. Also the water separator block isn't there on the Davv..