ODB DCL800TM, Owner'S Manual

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ODB Company
DCL800TM
5.1 Engine Electrical Troubleshooting Guide
ENGINE RUNS ONLY WHEN OVERRIDE BUTTON IS
DEPRESSED
Make sure the PTO is disengaged.
1. Take a look at the limit switch located at the inspection door of
the blower housing. Check to be sure that the inspection door
closes completely and that the door presses in the limit switch.
The limit switch is extremely sensitive and only needs to open
1/64” to shut the engine off.
2. If the inspection door closes properly and presses in the limit
switch properly, then disconnect the two wires from the back
of the limit switch.
3. Start the engine using the normal procedure then release the
shut off button. If the engines continues to run then the prob -
lem lies in the limit switch or the limit switch wiring. If the
engine still cuts off then the limit switch is not the cause, go to
Testing the shut off switch.
TO TEST THE LIMIT SWITCH:
4. With an ohm meter check the resistance of the terminals A &
B (Fig. 1) while the button is not depressed. There should be
no resistance or continuity. With the button depressed there
should be full continuity or infinite resistance, if not the switch
is bad and should be replaced.
TESTING THE SHUT OFF (MURPHY) SWITCH:
5. Turn the ignition switch to the first position.
6. Put a test light to terminal B (Fig. 3) to test for current. If there
is no current at B, power is not getting to the shut off switch.
Then the problem is not the shut off switch.
7. If there is current at terminal B, put a test light on the fuse
at location Z (Fig. 3). If there is no current there the fuse is
blown. Replace fuse.
8. If there is current at B and Z, push the override button (let-
ter X, Fig. 3) in on the shut off switch. While the button is
depressed place the test light on terminal C (Fig. 3). If there
is current at terminal C then the shut off switch is functioning
properly and the problem lies elsewhere. If there is no current
at terminal C then the shut off switch is defective and needs to
be replaced.
9. Next locate the fuel solenoid valve located on the fuel injector pump (Letter C, Fig. 2). It has an orange wire run-
ning to it. Pull the ignition switch to the first position. Put a test light on the terminal of the fuel solenoid where
the wire is attached. Test light should light up showing current, if not shut off switch is bad. Replace.
10. If engine still cuts off after shut off button is released then test the water temperature switch (located on the engine
block, Letter D, fig. 2) by removing the brown wire attached to the temperature switch. Start the engine using
the normal procedure then release the shut off button. If the engine continues to run then the water temperature
switch is defective. Replace the switch. If the engine shuts off, do the same test on the oil pressure switch. If the
engine continues to shut off after this test call ODB for additional service procedures.