Vacuum Pump Oil - Closest substitute??

[davefr]

What's the closest substitute for Vacuum Pump oil that can be purchased at "normal" stores?

I know I can get vacuum pump oil shipped to me from speciality suppliers but if I choose to use an off the shelf product, what would be the closest fit?

This is for a Welch Vacuum pump I got at a garage sale. It's used for evacuating air conditioning systems.

 

[Steve S]

I have an old Snapon pump that looks like a refrigerator pump and the sticker recommends 10w/40 motor oil.

 

[salesrep]

I'd think about a hydraulic/compressor fluid. iso???? 32???

 

[Ugly3]

Vacuum pump oils are pretty specialized. Best to get the right stuff.

Vacuum Pump Oil

 

[Pushslice]

Not familiar with Welch, but most larger industrial rotating vane VPs (e.g. Fuller) take an ISO 150 oil, either hydraulic-type or R&O type.

 

[tdi-rick]

If I'm out of vacuum pump oil, I use a refrigeration oil like Suniso 3GS, which is 155 SUS/38*C in a twenty five year old two stage Robinair pump