Generac Power Systems 5414, 5412 Test 14 - Try Cranking the Engine, Test 15 - Check Fuel Pump

Section 7

DIAGNOSTIC TESTS

Test 14 – Try Cranking the Engine

DISCUSSION:

If the Start-Stop Switch on the generator panel is actuated, but the Fuel Pump does not run (priming function doesn’t work), perhaps battery voltage is not available.

PROCEDURE:

Hold the Start-Stop Switch at “START”. The engine should crank and start.

RESULTS:

1.If the engine cranks normally, but the priming function still doesn’t work, go to Test 20.

2.If engine will not crank, go to Test 16. Refer to Problem 6 of Section 6.

3.If engine cranks but won’t start, go to Problem 7 of Section 6.

4.If engine starts hard and runs rough, go to Problem 8 of Section 6.

Short to Ground:

6.To test for a shorted fuel pump coil, connect one test lead to the Red Wire (Pin 2 of Connector 2, see Figure 7-14). Connect the other test lead to the fuel pump housing. “Infinity” should be mea- sured.

Test 15 – Check Fuel Pump

DISCUSSION:

An inoperative Fuel Pump will (a) prevent the priming function from working and (b) prevent the engine from starting.

PROCEDURE:

1.Remove Fuel Filter and verify that filter is not clogged. Replace filter if necessary.

2.Verify that fuel is available to Fuel Filter inlet. Use an alternative fuel supply if questionable.

3.Remove air filter access panel and air filter. Remove fuel hose from pump. Place a suit- able container to catch fuel from fuel pump line. Activate fuel primer switch. Pump should operate and fuel should flow. If pump does not operate, proceed to Step 4.

4.This step will test the ground wire. Disconnect Connector 2 at the Fuel Pump. Set the VOM to measure resistance. Connect one test lead to the Black wire, (Pin 2 of Connector 2) that goes to the Control Panel (see Figure 7-14). Connect the other test lead to a clean frame ground . “Continuity” should be measured.

5.To test for an open fuel pump coil, connect one test lead to the Red Wire (Pin 1 of Connector 2) going to the fuel pump. Connect the other test lead to the Black Wire (Pin 2 of Connector 2) going to the Fuel Pump (see Figure 7-14). The VOM should indicate Fuel Pump coil resistance of about 29.5 kW. (Current draw of the pump at nominal voltage is approximately 1.4 amperes MAXIMUM).

Figure 7-13. – Electric Fuel Pump

RESULTS:

1.If “Continuity” was not measured in Step 4, repair or replace Wire 0 between Connector 2 and the ground terminal.

2.If “Continuity” is measured in Step 4, but pump does not operate in Step 3, replace the Fuel Pump.

3.If the pump fails Step 5 or Step 6, replace the Fuel Pump.

Note: If desired, a pressure gauge can be attached to the pumps outlet side. Pump outlet pressure should be 2.0 to 3.5 psi.

4. If the pump operates normally, go to Test 28.

PIN 1 - RED WIRE

PIN 2 - BLACk WIRE

Figure 7-14. – Harness to Fuel Pump

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