Compressor oil which is the correct one?

Many of us have the smallish 4500psi compressors that have a crankcase and require oil. Some even have the higher quality Alkin, Bauer or Coltri units.

These compressors are not just plain Jane compressors but are usually referred to as "dive compressors" as they put out 4500psi or better.

Although I have in the past used ISO 46 or regular Husky brand synthetic or synthetic blend compressor oils, in my Yong Hengs, and have not had a problem others have. I kind of knew this could be a problem already but a post from another member really brought it home to me. I eventually repented of this evil I had been involved in and put the correct oil in my compressor. 

Plainly, if you do the research, regular compressor oil is not the correct lubricant for the high output compressors, we are using, that often see pressures near 4500psi.

Regular compressor oil is good for regular compressors where the pressure output is in the 100 - 150psi range. 

When I finally decided to stop being so stubborn about spending a little more money on oil I switched over to the Seco Lube 500 synthetic dive compressor oil. They make an 800 oil that is good for this application as well.

https://filtertechs.com/product-tag/seco-lube-500/

Mobile and Shell also make suitable lubes for the "Dive Compressors".

This just a reminder that your ISO46, Husky and Royal purple or non detergent motor oils are not the correct oils for the compressors we are using.

I am aware of a couple of compressors that were destroyed by detonation problems, some months back. Both were using the Royal Purple. Although I am not sure of the root cause of the detonation neither was using the correct oil.
 
I have had my Yong Heng almost 2 years now and have only used Royal Purple without any issues. That said, I do agree with you 100% that it’s not the correct oil for the compressor. I had planned on switching over to the correct oil with my next fluid change. I certainly would only run oil designed for a high pressure compressor if I bought a new one today. Here is something to ponder...how much longer would one of the Yong Heng compressors last if you only used the correct oil, assuming you got a good one? I would also like to know the percentage of owners that use the high pressure compressor oil, I bet it’s very low. These things might be much better than what we are seeing due to not using HP compressor oil. How many Bauer, Alkin or Coltri owners use Royal Purple or something similar? I bet it’s not many. Now I’m not implying that the Yong Heng is anywhere close to the same quality as the premium compressors, because they aren’t. But they could be a much better compressor than we think they are.
 
I have been using royal purple in both my yong heng and my hatsan lighting for 3 years and never had a problem. The compressor we use run on a crank shaft and oil in the case just splash around to lube the shaft. The oil should never go into the high pressure side. So as long as it is recommended by the manufacturer. It is ok to use. Dont need high end bauer compressor oil. I called hatsan and asked them what oil to use. They said any iso 100 compressor oil is good enough so that is good enough for me. We aren't running $4000-6000 compressor so why should we need high end compressor oil? 
 
Got my seco lube 500 saturday from filtertechs. Live in Florida ordered Friday afternoon here Saturday.going to be using in yong Heng and tuxing txedtO32 read a lot on here and talked to other forum members iflyskyhigh helped me and recommended seco lube. Did some research and decided to take his advice. Went with 500 over 800. Some say 800 will gunk up in high humidity. 800 is made for hot dirty environment but maybe not humidity. I don't know which is best. Maybe someone on here can give more input on difference. I also used the iso 46 on my yh for two years with no problems. But not anymore. New compressor comes tomorrow that's why I bought the seco lube. I didn't know two years ago but now want good oil to protect investment. And will give yh new oil.
 
I have been using royal purple in both my yong heng and my hatsan lighting for 3 years and never had a problem. The compressor we use run on a crank shaft and oil in the case just splash around to lube the shaft. The oil should never go into the high pressure side. So as long as it is recommended by the manufacturer. It is ok to use. Dont need high end bauer compressor oil. I called hatsan and asked them what oil to use. They said any iso 100 compressor oil is good enough so that is good enough for me. We aren't running $4000-6000 compressor so why should we need high end compressor oil?

ImpactX, I have to disagree with your thoughts on this subject. Yes the oil’s primary function is to lubricate the bottom end of the compressor, but the crankcase oil DOES get into the low and high pressure compression stages of the compressor. It comes up past the piston rings on the first stage and also on the second stage on a two cylinder compressor (Hatsan Lightning that we both own). Every time we purge the output side of our compressors during a fill session we get moisture, but it is not just moisture, it is an oily mix of condensation and oil. Every time we service the cotton filter on the coalescing filter (gold filter on the Lightning) or little tampon filter on the YH we see not only moisture but it is also darkened and slimy with oil residue. That oil can only come from one place… the crankcase. It’s not from the air we are feeding into the compressor. The benefit of running the specialized high pressure compressor oil is that it has a higher flash point, typical ISO 46 = 440F, Royal Purple = 460F, and SecoLube 500 = 520F. In our very specialized high pressure compressors we definitely want to run oil that has a high flash point to avoid carbon buildup and the possibility of detonation.



When I had a failure on my Lightning at only 7 hours of runtime (low output pressure / Royal Purple in crankcase) I found carbon on both the high and low stage pistons. Particularly on the high stage piston there was a carbon build-up that looked very much like what you would find on the piston of an internal combustion engine. It was relatively hard and took some work to scrape off of there. The low pressure piston also had a little bit of carbon and was also wet with oil. The failure point that I found was the check valve on the high pressure stage had carbon buildup that was holding the check valve open. I cleaned out the carbon, put it back together and all was right with the world. This is when I did my research on compressor oil that is made specifically for high pressure compressors and made the change to SecoLube 500. I am right at 8 (more) hours of runtime since my repair so it is a little early to tell if the oil will make a difference, time will tell. Yes it takes about $30 to get a quart of SecoLube 500 on your doorstep, but in the big scheme of things with airguns that’s a drop in the bucket!

Chip


 
Agree with findings of this thread and plan, as Cannonball, to switch at next oil change. My question is, why members, running 460F flash point compressor oil, go years without problems, while others loose machines? My best guess is that it relates to run temperatures. With gun-only fill, external fan assist and well-chilled water, my Yong Heng never reaches 50 degree Celsius, according to OEM temperature sensor read-out. Is it possible some just aren't reaching the flash point temperatures required for detonation? WM
 
WorriedMan, I think you are spot-on with your thoughts. I think run temperature and also what folks choose as a max pressure to run their compressors up to are the biggest factors. Probably people that choose to run up the the full 4500 PSI are also at a higher temperature when they shut down and those two variables are what causes the detonation. I believe the best way to make any of the 'non commercial' compressors live a long and happy life is by doing everything we can to 'baby' them just a little bit.

Chip
 
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Deacon,

Got it, makes better sense, that way. Like TN_Yankee, gallon too much for me, even a quart will last 3 years @ 10 ounces per oil change.

Chip,

You seem like a knowledgeable guy with an ability to articulate well, in addition to treating fellow members with respect and decency. I'm afraid I'll have to give you a plus one for Accuracy. Well done, sir. WM


 
Boy I see the thinking n both sides. I agree with the post above on running the max psi is the biggest problem.
I have been running RP with out any problems. But then again I only fill my guns not a tank and I only fill to no
more than 3800 psi. I see no reason to push the envelope more than that. My aea rifles recommend 3600 psi
as does my Avenger. Plus I do not want to put any more load on my small Tuxin than needs to be. But when I
use up my RP I will most likely change.

Fly.
 
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