cheap compressor lubricants (what oil do you use and why?)

[Jorgo]

I try w30 ...iso 46...w50 and last time i use w40 and it dont change to dark like the others

I let it much longer in bevor i change 2 or 3 hours

 

[Eaglebeak]

I contacted the technical department of oil company that specializes in performance lubricants. I was told that synthetic oil has a similar flash point to mineral based oils which means that it is no less likely to diesel in high pressure environments than mineral based oil. I was also told that the only major advantage that synthetic has over mineral, is the longer change intervals. 4000 hours against 2500 hours. The primary purpose of the oil is lube the crank pin and big and little ends. I am yet to see a worn out bearing in one of these pumps. I have seen numerous electrical and piston failures, none have had anything to do with what oil is used. For the people that have to use the most expensive oil they can find and change it every half hour, I say knock your socks off if it makes you sleep better at night. I for one are using ISO 68 compressor oil. I changed it after the first 11/2 hour break in period, and won't be changing it again, unless of course the pump lasts 2500 hours. There is definitely a problem with QC issues, but the major cause of trouble with these little compressors, is operator ignorance.

 

[Saltlake58]

Since the cheap compressors have no oil filters, might make sense to tape a rare earth magnet to the crank case to attract any metal filings. The cheap compressors have rubber rings that will deteriorate over time, so changing oil frequently will be a must.

Can't imagine "decoking" an engine. Sounds like lots of caustic solvents and scraping. Lots of really dirty work!

 

[Saltlake58]

Eaglebeak - what are you using, and how many hours do you have on the current oil change?

 

[heavy-impact]

I contacted the technical department of oil company that specializes in performance lubricants. I was told that synthetic oil has a similar flash point to mineral based oils which means that it is no less likely to diesel in high pressure environments than mineral based oil. I was also told that the only major advantage that synthetic has over mineral, is the longer change intervals.

Really.... exactly which group/base stock and additive package was he referring to? That's a pretty big blanket he threw over the lot. Would you call 25% higher flash point similar?

Additives usually fail long before the base oil, be it mineral or synthetic.

 

[Eaglebeak]

Eaglebeak - what are you using, and how many hours do you have on the current oil change?

I'm using a generic brand compressor ISO 68 recommended for all rotary screw, rotary sliding vane and piston type compressors. Here in Australia, this is the only type of compressor oil, that is readily available in containers less than 5 gallons. I suspect that it is 30 weight non detergent motor oil. Special nontoxic oils are recommended for breathing quality air, but they aren't needed for air gun use. So far I have about ten hours on mine. I don't use ice and the temperature never excedes 50 C, even filling a 6.8 litre bottle from 3000-4500 in the middle of summer. Durin the breakin period, The temperature would go as high as 58 C but since then, it stablizes at about 45 C. I recommend at least 4-5 gallons if you don't want to change it whilst filling.

 

[Saltlake58]

Eaglebeak - Thanks for the insight. Appreciate it.

I plan on buying a compressor in a couple weeks when it warms up a bit. While you are in the midst of summer, it warmed up to 0 Degrees C today. Must admit that I'm a bit of a wimp when it comes to cold weather.

I found a cross reference chart that says ISO 68 is SAE 20W ISO 46 is just SAE 20. An explanation of the "W" is here:

http://www.upmpg.com/tech_articles/motoroil_viscosity/

I've used Synthetics in my cars since Mobile 1 was introduced in the late 1970's, so I'll probably run a synthetic version of the oil here. In the early days, I ran some mileage tests in my car, and the Synthetic did reduce friction.

Also interesting, read the explanation about synthetic oils towards the bottom of the article. This verifies what the techs said about the flash point of synthetics vs regular oils. Most synthetics, including standard Mobile 1 are now based on regular oil products. Other synthetics seem to be based on something else, like Carbon Dioxide, methane, and some other stuff. Chemestry beyond me in this case. So it looks like the best synthetics are PAO or Polyalphaolefin based oils. It's more expensive than regular, so few companies make it.

Regardless of the base, if the synthetic oil is based on regular oil then the flashpoint should be the same.

I've been down-under twice. It was fun to fly out of Salt Lake at -5C and fog, and arrive in Brisbane with 28C and sunny. Beautiful place, though I do wish I'd had time to see Darwin and the Outback. Spent most time in Brisbane, with some time in Perth, Melbourne, with a blazing 8 hours in Sydney between flights. Beautiful place, and the wife has an Opal I picked up from a Gem shop in Brisbane. Someday, I might get back! It was unique to go for a walk around Brisbane and see Wallaby's hanging around the hotel. You don't get that up here. 

Thanks again for the info. It all makes sense.

 

[Eaglebeak]

I contacted the technical department of oil company that specializes in performance lubricants. I was told that synthetic oil has a similar flash point to mineral based oils which means that it is no less likely to diesel in high pressure environments than mineral based oil. I was also told that the only major advantage that synthetic has over mineral, is the longer change intervals.

Really.... exactly which group/base stock and additive package was he referring to? That's a pretty big blanket he threw over the lot. Would you call 25% higher flash point similar?

Additives usually fail long before the base oil, be it mineral or synthetic.

The oil company technician was only referring to only the oils that they make. I assume that other companies adhere to similar specs and additives. I doubt that other companies change intervals would be much different.

 

[heavy-impact]

The oil company technician was only referring to only the oils that they make. I assume that other companies adhere to similar specs and additives. I doubt that other companies change intervals would be much different.

All oil companies don't produce the same products, the big difference in price is for good reason. My oldest son is a lab tech for one of the big players.

 

[Centercut]

I highly recommend Royal Purple Synfilm Air Compressor Oil. If you don't use that, at least use a quality 100% synthetic 30W motor oil. I am currently working on reviewing and assisting in the manual for the Tuxing two cylinder compressors with @josoo. The above is what we will be recommending. Whatever you do, DO NOT use the #46 hydraulic fluid that "used to be" recommended by some of the manufacturers like Yong Heng. This is not the correct fluid for any compressor; it is much more like brake fluid than lubricating oil, and is used in hydraulic systems as the pressure transfer medium...

FYI, ISO 100 is equivalent to SAE 30. So ISO 46 weight fluid is approx. SAE 14, very thin...

 

[Saltlake58]

Centercut - The Yong Heng's currently advertised recommend a ISO 46 oil, why move to an ISO 100 when the manufacturer recommends a ISO 46 oil. AMSoil makes a ISO 46 Compressor Oil - full synthetic. Why not use the full synthetic in the recommended weight?

My car recommends 5-20, so the newer oils can handle punishment. Just wondering why the manufacturer's recommendation shouldn't be followed?

 

[Centercut]

What I read is that they recommend an ISO 46 hydraulic fluid. Using an ISO 46 100% synthetic compressor oil is perfectly fine. What I've found is that Yong Heng and other manufacturers like Tuxing have a problem with the translation from Chinese to English. FYI., the manual that I initially reviewed was rife with errors that were mainly due to the language barrier.

Just a consideration, but the tolerances on your new car are much tighter than those on the Chinese compressors, plus the new car I'm pretty sure uses roller bearings vice cheap journal bearings like the inexpensive Chinese compressors. So due to that, my recommendation to Tuxing was to go with the slightly more viscous ISO 100 (SAE 30) weight oil. Kinda like using the 10W-40 or 15W-50 in an older car that doesn't have the tight stack up tolerances like most new cars...

 

[Saltlake58]

Many thanks, language and what I believe was referred to as "Chenglish" can be really confusing.

 

[Eddie_E]

Chinese companies sometimes pick oils based on pricing in their home market. An example of this is that at least two companies making motorcycle engines used fish oil in the crank case. Yes, I said FISH OIL. One of those companies has been an OEM builder for Honda motorcycles.

All the Americans I knew who bought one would break in engines for 3 minutes then dump the fish oil before filling with proper oils and racing it. The first dump ALWAYS had metal shavings.

 

[heavy-impact]

Most people in China do not change the oil in their car and think it's a waste of money to do so. They also reprocess cooking oil from the sewers to be cooked with again by some street vendors. They call it gutter oil. China is very different from the west.

 

[moonlitnite]

At least we should be gratified our compressor air is used for air rifles, etc. The oil used by our SCUBA brethren costs more that twice high grades like Royal Purple synthetic oil... but then who would want to be constantly breathing stinky hydraulic oil in their lungs for an hour or more underwater?

https://www.scuba.com/US/scuba-gear-161/080045/Max-Air-Maxlube-501-Compressor-Oil-1-Gallon.html?gclid=Cj0KCQiAjszhBRDgARIsAH8KgveutmcqGH6dFcK9pJ3CpipISHW3YepibFkvIPFWeYs6Vb5D8VLA9J4aApzeEALw_wcB