Generac Power Systems 5415 Test 37 - Check Wire 86 for Continuity, 44. - Oil Pressure Switch

Section 7

DIAGNOSTIC TESTS

Figure 7-44. – Oil Pressure Switch

PROCEDURE:

1.Check engine oil level. If necessary, replenish oil level to the dipstick “FULL” mark.

2.Set a VOM to its “Rx1” scale and zero the meter.

3.Connect the meter test leads across the switch terminals, with engine shut down. The meter should read “Continuity”. A small amount of resis- tance is acceptable.

4.Crank the engine. Oil pressure should open the switch contacts at some point while cranking and starting. Meter should then indicate “Infinity”.

5.If the contacts did not open in Step 5, remove the low oil pressure switch and connect an oil pressure gauge in it’s place. Start the engine and measure oil pressure. Pressure should be above 10 psi.

RESULTS:

1.In Step 3, if “Continuity” is not indicated, replace the switch.

2.If oil pressure checked good in Step 5, but Step 4 measured “Infinity,” replace the low oil pressure switch.

3.If oil pressure is below 10 psi, determine cause of low oil pressure. Verify that the oil is the proper viscosity for the climate and season.

4.If all steps check GOOD, go to Test 37.

Test 37 – Check Wire 86 for Continuity

PROCEDURE:

1.Disconnect the J1 Connector from the Printed Circuit Board.

2.Locate Pin Location J1-6 on the harness end of the J1 Connector.

3.Remove Wire 86 from the Low Oil Pressure switch (LOP).

4.Set a VOM to its “Rx1” scale and zero the meter.

5.Insert one meter test lead into the end of Wire 86 disconnected from the LOP. Insert the other meter test lead into Pin Location J1-6 on the harness end of the J1 Connector.

RESULTS:

1.If “Continuity” is not indicated, repair or replace Wire 86.

2.If “Continuity” is indicated, replace the Printed Circuit Board.

Test 38 – Test Oil Temperature Switch

DISCUSSION:

If the engine cranks, starts and then shuts down, one possible cause of the problem may be a high oil temperature condition. Protective shutdown is a nor- mal occurrence if the oil temperature switch exceeds approximately 270° F for gasoline units, or 284° F for LP units.

Figure 7-45. – Oil Temperature Switch

PROCEDURE:

1.Remove Wire 85 from Oil Temperature Switch terminal and start the generator. If engine starts and runs now, but shuts down when Wire 85 is connected to the switch terminal, the following possibilities exist:

a.Oil temperature is too high.

b.The oil temperature switch has failed closed or is shorted to ground.

2.Remove the switch and place its sensing tip into oil (Figure 7-46). Place a thermometer into the oil.

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