Standard small engine (single cylinder, 4 cycle, 3 to 14 hp) rpm is
3600, some later engines run a few hundred RPM faster.


http://www.northerntool.com/webapp/w...70_14323_14323

Most of the pumps I found were rated at 3450 to 3600 RPM for full
output. Note that you can get trash pumps, semi-trash pumps, clear water
pumps, and high pressure pumps.

Yours appears to be a semi trash variety. This is good for some soft
solids like an occasional leaf or bird dropping, high volume, lower
pressure.


Karl Townsend wrote:
I just bought a trash pump without the gas engine.
http://tinyurl.com/d3qj5f

What RPM do I spin it at?

FWIW, I hate small gas engines. Nothing but trouble. I'll use a 3 phase
motor for this job.

Karl