Question for members who have bought YONG HENG compressors on ebay

hunt junky which version do u recommend ?IMHO don't mess around with ebay or local supplier. $100 more for compressor/shipping. Try online @ Ali Express and purchase through "Yongheng Shop Store" or "White 'Whale Mech". Received within 10 days of order approval and they have all maintenance/repair components. Great service and good communication. You'll have to create an account but the same applies to ebay, amazon, etc. Cut out the middleman and save the upcharge. You'll thank me later.
https://www.aliexpress.com/item/300BAR-30MPA-4500PSI-High-Pressure-Air-Pump-Electric-Air-Compressor-for-Pneumatic-Airgun-Scuba-Rifle-PCP/32815880523.html?spm=2114.10010108.1000014.17.40bd3c4db4uTMD&traffic_analysisId=recommend_3035_null_null_null&scm=1007.13338.80892.000000000000000&pvid=3c4cb1d8-0839-4598-8672-6fea662c3ee4&tpp=1
 
Just got my second Yong Heng pump. (lost first one, with 3 minutes on it, in my house fire. Switched out the electrical plug on it and bought/installed battery in temp gauge; filled with #46 hydraulic oil. Turned it on and it started seizing in 10 minutes. Lucky me!
Can't find a parts source on line for gaskets, connecting rod, etc; anyone have a link??
 
 It is so explicit in different manufacturing manuals to use 46 hydraulic instead of non-detergent oil, there must be some reason other than translation. I have considered this since reading it. I am myself using 46 hydraulic. The only reason I can come up with is the temperature range combined with the extreme pressure’s. But a good Compressor oil should not break down either. Could it be due to the unusual 2 stage single shaft engineering of these units? 

Are you saying that you use standard 30 weight non-detergent oil? Not even a 40? 
 
I use Royal Purple Synfilm Air Compressor oil. It is approx equivalent to 30 wt motor oil in viscosity. FYI, ISO 100 is the equivalent of SAE 30. So your ISO #46 hydraulic fluid is equivalent to less than 15 wt motor oil. The hydraulic fluid will burn, turn black and gum up in high pressure air compressors. Always use 100% synthetic oil. 
 
I've been using normal compressor oil the same stuff that I use in my cheap Chinese shop compressor. It's got an ISO rating of 68. I expect that the electric motor will cark it before the big end. So far I've topped my bottle off about 4 times and it has about an hour and a half of run time on it. The oil is still clear but I will probably change it soon to get rid of any metal filings or chunks. Yes, synthetic is better but good old mineral oil is adequate for a crude loose tolerance machine like this. I've got no idea whether synthetic oil is any less explosive under pressure than the normal stuff but I suspect it is much the same. By the way, the Yong Heng has exactly the same crankcase as my shop compressor. The shop compressor probably has the same conrod and crankpin setup as well. It does, however, have a larger motor bolted to it. I agree with Centercut about using hydraulic oil, it is for hydraulics, lubrication is a secondary function.