What oil are you using in the Yong Heng ?

I'm thinking about using Chemlube 751 or 501 , the 751 is sae 40wt. and the 501 is sae 30wt. I'm getting my new compressor this week and want to start off on the right foot with the right oil . Does anyone know what ISO the oil should be ? Thanks and sorry to open this can of worms again but there are a lot of different opinions . I think I would be OK using a good synthetic made for high pressure compressors but let me know what you use. 
 
3+ years and no problem.
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ISO 46 may no longer be recommended although I used it for a year without failure. I am currently using the Husky Brand Synthetic or synthetic blend oil, found at Home Depot, for two years now without a problem. Top it off to the red circle in the sight glass. This oil is clear so you can see when it gets contaminated.

After some werq on my YH I fergot to put any oil in it and ran it for several minutes without any. It actually survived the ordeal likely because of the oil it had in it prior.
 
I switched to Chemlube 751 after using the royal purple for about an hour. I pulled the front cover when I switched, and it had a odd smell, almost like cordite which may have indicated detonation with the royal purple? I’ll pull the cover again at the next oil change and give it a smell. I have not experienced stink air as some report. 
 
lol another oil thread ... i got the royal purple because thats what came up on the suggestions on amazon when i ordered it and i didnt feel like looking around ... i would definitely worry about heat, moisture and what kind of duty cycle you inflict on it and pretty much not worry about the oil, its going to have very little to do with how long it lasts as long as its the proper type .. maybe change it occasionally if your skeerd .. trust me it wont save it from improper treatment ..
 
Your best option is soft water but not distilled as the purity of distilled can cause erosion, soft water is free of the calcium and magnesium that causes scale to form, but not so pure as to cause erosion of the cooling jacket and fittings.

Why not use "antifreeze" with additives to prevent corrosion? Most cars have aluminum blocks cuz they are lighter and aluminum transmits heat (out), better than cast iron.

Just curious.....
 
I don't see any problem with using a very small amount of coolant, I just wouldn't add very much. Between a little coolant and Red Line water wetter, it will help prevent algae from forming in the cooling bucket as well as limit corrosion of the aluminum parts. ( for those who don't change the water each time)

As a side note, I started out using the full synthetic Husky compressor oil in my YH when it was new, but after experiencing detonation and a broken 2nd stage piston, I moved to a better oil. Yall do as you like, no Royal Purple or Huskey for me, and I no longer get the crackling sound I used to get when I used the Huskey. YMMV.