A 1 quart oil bottle and a vacuum/pressure gauge- - - -total investment less than 20 bucks. Every shop needs that gauge. Like the slogan Sun Electric Co. used to put on all their equipment- - - -"We test, not guess!"

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The pump should produce at least a pint of volume in 30 seconds at idle speed, make 2-4 PSI of pressure and hold it for a short time after engine shutdown, and hold at least 12 inches of vacuum on the suction side for a short time after engine stop. If it passes the pressure and vacuum test but is short on volume, fix the restricted fuel line between the gas tank and the pump. A collapsed flex line between the frame and the engine is a good place to start looking.
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!