Oil recommendations for Yong Heng compressor

Just ordered a Replacement Yong Heng and a gallon of Seco 500 Including shipping to California $86.00. My current Yong Heng, I just took apart because it quit compressing and gave her a good cleaning of the head and ports. I was using the Husky Full Synthetic and pretty clear evidence of carbon, so it's making it's way up into the second stage.
I think I'll be keeping the new one going only to 4,000 PSI, I have a small CF Omega bottle to keep filled so not that big of a deal for the extra 500 psi, why push it.
 
Just ordered a Replacement Yong Heng and a gallon of Seco 500 Including shipping to California $86.00. My current Yong Heng, I just took apart because it quit compressing and gave her a good cleaning of the head and ports. I was using the Husky Full Synthetic and pretty clear evidence of carbon, so it's making it's way up into the second stage.
I think I'll be keeping the new one going only to 4,000 PSI, I have a small CF Omega bottle to keep filled so not that big of a deal for the extra 500 psi, why push it.
No need to limit it since 2000psi is enough to destroy parts through detonation. If you want to be easy on it just pump in stages letting it cool when the temp exceeds 55c or so. Be sure to restart it with a bleed valve open. The high flashpoint oil was a good move.
 
Ok so what makes Seco lube 500 better than mobile Rarus 827? lm not saying you are wrong, just want to see the
data.
Fly
I did not say Seco lube 500 is better than Rarus 827. I merely suggested the VI is a more important base line when considering high pressure compressor oil. As a retired hydraulic engineer I used and recommended Mobil DTE heavy medium oil all the time. The zinc and phosphorus content was very high making it ideal anitwear property but not for a compressor. I would need to research Rarus 827 and compare test data. If this is a Mobil mfg product I would likely see all the data on their web page. You need to research and make your choice. For me, it's Seco Lube 500. Having been to China many times I can tell you they excel at volume production at low cost. However, there tolerance and metallurgy are poor and inconsistent. You can have the absolute best compressor oil but if the mechanicals are substandard it will fail. The tolerance stacks they use is good on paper but not on the shop floor. My 2.5 cents worth. Take care
 
I just rebuilt my YH two days ago with migrating parts between the old and new compressor. I had a cracked oil pan and didn't wanted to irritate the seal on the crank shaft so I moved the upper two cylinders other way around to the new pump.
About ten hrs on the first and second stage and the carbon buildup was visible pretty aggressive on the high pressure piston, vs the old piston w some 30+ hrs runtime, I put the old piston back and will try to educate myself for future how to replace the rings.
I am using RoyalPurple in the past 2-3 years, not because I like it but this what I bought couple bottles back then.
I think synthetic oil is synthetic oil shall not make a big difference in a $300 compressor.
But honestly I am using the best Mobile1 in my $45K Audi.
 
Just ordered a Replacement Yong Heng and a gallon of Seco 500 Including shipping to California $86.00. My current Yong Heng, I just took apart because it quit compressing and gave her a good cleaning of the head and ports. I was using the Husky Full Synthetic and pretty clear evidence of carbon, so it's making it's way up into the second stage.
I think I'll be keeping the new one going only to 4,000 PSI, I have a small CF Omega bottle to keep filled so not that big of a deal for the extra 500 psi, why push it.


Wish I knew about RARUS 827, I did the same thing and have a gallon of the Seco 500 oil which will last me basically forever. LOL!!!

I followed @heavy-impact and @biohazardman advices on oil, start/stop with bleed valve open and after 2 years the only problem I had was a broken gauge but now my temp meter is out of battery or has loose contact. Couldn't be happier with the results, big thanks to those 2 and all others who have helped with great information. (y)(y)(y)
 
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The bigger issue for me was going to shoot last weekend and not having any air. The oil I'll use for these two and when they die and get replaced by a nicer unit, I'll still have a quality oil for it.
From 150 bar up to 300 Bar it was only taking around 5 - 6 min to get there.

I'm surprised that people heat cycle these units. Once a product reaches thermal stability it should be able to run all day long with no issues. Mine used to get up a little over 50ºC and then kind of plateau.

Smitty
 
I think synthetic oil is synthetic oil shall not make a big difference in a $300 compressor.
But honestly I am using the best Mobile1 in my $45K Audi.
I agree with the above & no argument from me. Discussion yes, l'm about doing the right thing in keeping
my compressor going with out any more trouble or cost then necessary. I will do more research on the
Mobile oil but for now I see no disadvantage with it & at a lower cost.

Fly


Synthetic is not always synthetic in the USA. Our government allows petroleum oils to be called synthetic if they meet a certain standard.
Rarus 827 and Seco 500 are Diester oils with a considerably higher flashpoint than Amsoil or Royal Purple and won't produce the carbon that lower grade oils leave. The price of the compressor has nothing to do with the operating parameters of the oil. Use the right product and you'll get a much longer life from the compressor. One quart does at least 3 oil changes so the cost isn't significant.

Never use detergent oil like mobil 1 in anything without a filter. Detergent oils keep contaminants suspended in the oil so a filter can remove them on each pass through the oil pump. Non detergent oils like our compressors need do not contain dispersants and let contaminants settle to the bottom of the sump where there stay for the life of the unit or until removed manually.

Just about any oil will keep these compressors alive untill they get enough wear for oil to start making it's way to the high pressure piston at which point low grade oil will start building up carbon and detonating until it caves in the top of the big piston and wipes out the top of the skinny brass piston.
 
This is the oil I use in my YH.

Nuvair 751 Paintball & Industrial Air Reciprocating Compressor Oil



751_1.1641404949.jpg





Here is the data sheet for it

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View attachment Nuvair_751_2019.1641405437.pdf
 
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Since this is an old thread I'll add that Royal Purple is no good for the yong heng and will definitely detonate and destroy the big and little piston. I learned the hard way. I recommend Seco lube 500 as well, it's the only oil I use in my compressors now. https://filtertechs.com/shop/oil-media/compressor-oil/cl-581812-lq/
I second this recommendation. I ran Royal Purple compressor oil in mine and it was dieseling in the second stage. Thankfully mine compressor started maxing out around 3700 psi after 10 hours of runtime which caused me to take it apart. The reed valves in the head were covered with carbon and soot which prevented them from sealing. The top of the second stage piston was also starting to unscrew and come loose, but wasn't damaged. I replace the second stage piston rings and cleaned the reed valves and the metal disk they seal against. Now it runs like new. No more Royal Purple in my YongHeng.

I wonder why it seems to work better for some people than others?
 
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I also use Nuvair 751. It's flashpoint is 522 F. I recently took my YH apart because it was leaking air making it harder to pump my 45 minute SCBA tank up to 4000 or more. It needed a new O-ring. The high pressure piston had a bit of black deposit on it. Looked like carbon but wiped right off. Might have been somewhat broken down oil. The high pressure piston showed essentially now wear. After reassembly I pumped the tank up to 300 bar in about 15 minutes with the pump temperature staying well below 60 C.

I change my lube once a year in the YH. I fill my tank about once a month. It may need changed more often if you fill bigger tanks or more tanks. I think it should be based upon run time. Not sure the best criteria but mine is getting changed every 5-10 hours run time. Seems to be working.
 
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I second this recommendation. I ran Royal Purple compressor oil in mine and it was dieseling in the second stage. Thankfully mine compressor started maxing out around 3700 psi after 10 hours of runtime which caused me to take it apart. The reed valves in the head were covered with carbon and soot which prevented them from sealing. The top of the second stage piston was also starting to unscrew and come loose, but wasn't damaged. I replace the second stage piston rings and cleaned the reed valves and the metal disk they seal against. Now it runs like new. No more Royal Purple in my YongHeng.

I wonder why it seems to work better for some people than others?
I have 7.5hrs on my Yongheng and am seeing a drop in compression. Will only fill to 250bar when filling my 9l tank. I too run Royal Purple. I'll be pulling it down probably next week and wee if I have the same issues you did. If so, Royal Purple s gone. Will have to find something else. Hard to get anything out of the ordinary locally.
 
The cost of the oil should never be a stressed out situation, or brought up for consideration. When the day comes and you’re either wrenching on your compressor, up all night sourcing parts, or having to buy a replacement altogether you’ll think back on the oil chosen and if you went cheap.

I’ve already accepted the fact most folks do it backwards and spend the big $$ on the Gun rather than the air source. At least pony up and give your compressor the best it needs, so as to guarantee a reasonable life span.

Reminds me of someone I know that used roofing nails instead of sheet rock nails in his room addition- it doesn’t work!