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Fuel Pump Performance Test (I-Mark)

  1. Disconnect negative battery cable. Remove fuel inlet hose from carburetor. See Figure . Connect a pressure gauge between inlet hose and carburetor with a "T" fitting.
  2. Reconnect negative battery cable. Start engine and run at idle. Note pressure gauge reading. Compare with specifications in the FUEL PUMP SPECIFICATIONS  table below.
  3. Stop engine. Disconnect negative battery cable. Remove pressure gauge and "T" fitting. Reconnect negative battery cable. Place fuel inlet line in graduated cylinder. Crank engine for 30 seconds.
  4. Compare results with FUEL PUMP SPECIFICATIONS  below. If not within specification, replace fuel pump. Reconnect fuel inlet line.
FUEL PUMP SPECIFICATIONS

Test Result
Amigo & Pickup (Pressure) 3.56 psi (0.25 kg/cm2 )
I-Mark
Pressure 3.8-4.7 psi (0.27-0.33 kg/cm2 )
Delivery (30 Seconds) 0.428 quart (0.4 liter)