Buy a piece of 3/8" round steel stock from the hardware store, and use a hacksaw, file, or a cutoff wheel to make a tang 3/16" wide and 1/2" long on the end. Spin the pump clockwise with a 1/2" variable speed drill motor and hang on- - - - -when the oil pressure comes up there will be quite a bit of torque on the drill motor.
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!