Water based parts wash

Simple Green

I use oderless paint thinner in mine.

beekeep

I have good success with Dawn dishwashing liquid. Warming the solution helps a lot, an immersion heater can do the trick. Suds are not too much of a problem, but if you want any dishwasher detergent will work well (with hot water, of course) though it can be somewhat harsher on the hands.