The best recirculating parts washer I've used was built out of salvaged materials. A recycled 30-gallon rear end lube drum was fitted with a stainless steel kitchen sink. The solvent flow was provided by a submerged automotive oil pump powered with a 1/4 HP electric motor scavenged from a floor fan. We mounted the motor above the back of the tub with a long, direct-coupled shaft running the pump at the bottom of the barrel. 1725 RPM is just about highway cruise speed for any oil pump. Plenty of volume, and the steel-geared pump will last forever. You stovebolt purists could even use a recycled 216/235 pump. Mine was a Ferd, IIRC.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!