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B.O. Irwin
Jul 19, 2011, 11:38 AM
Hi, What is the difference in a gravity feed carburetor & a pump feed carburetor on a briggs & stratton riding lawn mower engine? Can they be interchanged? I have a Nikki #796109 (gravity feed) on my mower & want to replace it with a Nikki #794572 (pump feed). Briggs & Stratton engine number is 31P7770299E1.
Thanks
B.O. Irwin

ma0641
Jul 19, 2011, 01:06 PM
Probably not if the pump feed is run off the engine.. It has a diaphragm to pressurize the fueel to the carb and runs off the cam or other eccentric. In a gravity feed, it is only the head pressure of the gas in the tank which is always above the engine. Model T and A Fords had gravity tanks, no fuel pump.