Fuel Pump Supercharged

Posted On: February 27, 2015

All supercharged fuel pumps have a 5/16″ elbow 12S734 at the sediment bowl pointed down.
From the sediment bowl going toward through the pump, the fuel outlet exits right or towards the hood; not straight or left toward the engine block.
The outlet fitting for all fuel pumps is a 5/16″ elbow fitting 12S733.

The first supercharged cars with Stewart Warner fuel pumps J10356.
Sometime in the 1935 year a switch was made to AC fuel pump J10426.
Both pumps bolt in with no modification.
Gasket for both is J1-253 to the crankcase.
Pump is secured with two SA506 hex head cap screws marked W or 30, and two 11S2 copper asbestos washer gaskets.

Supercharged fuel pumps need to sit at a 90 degree angle from its mounting place on the block, or parallel to the block as a means to allow supercharged drive shaft clearance.

Fuel line: fuel pump to carburetor

  • One 12S724  5/16″ Inverted Flare Inlet straight fitting
  • Two 12S704 5/16″ Flare Nut
    • One on the carburetor
    • One on the fuel pump
  • Fuel Inlet tube 2S5049 from the fuel pump is 5/16 inch copper and 24-1/2 inches long.

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