If you have to crank your engine a lot to fill the carb bowls after it has set for a few days, you may need a electric priming pump. Hook it up to a switched 12v. source, protected with a fuse, and operated with a momentary contact switch and your problems will be gone. Here are a few pumps that work well, are quiet, and fuel will easily flow through them when your mechanical pump is doing it's job.
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Universal Standard 5/16'' 90 L/h 4-7PSI 12V Electric Fuel Pump Self-priming US | eBay
1. TS16949 quality system certified manufacturer . 2. Full copper winding, unlike other inferior products that are made of copper-clad aluminum material. 3. Shut off pressure: 4-7 P.S.I. ; Voltage: 12V ; Flows: 90 L/h; Fit Hose Size: 5/16" ; Inlet and Outlet diameter: 8mm ...
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Mr. Gasket 42S Mr. Gasket Micro Electronic Fuel Pumps | Summit Racing
Free Shipping - Mr. Gasket Micro Electronic Fuel Pumps with qualifying orders of $109. Shop Fuel Pumps at Summit Racing.

Carter P90091 Carter Inline Electric Fuel Pumps | Summit Racing
Free Shipping - Carter Inline Electric Fuel Pumps with qualifying orders of $109. Shop Fuel Pumps at Summit Racing.