Service manual

GLOW PLUGS
DESCRIPTION
The glow plugs are wired through the preheat solenoid.
When
PREHEAT is pressed at the control panel this solenoid
should
"click" on and the glow plug should begin to get hot.
INSPECTION
To inspect the plug, remove the electrical terminal connec-
tions, then unscrew or unclamp each plug from the cylinder
head. Thoroughly clean each plug's tip and threads with a
soft brush and cleaning solution to remove all the carbon and
oil deposits. While cleaning, examine the tip for wear and
burn erosion;
if it has eroded too much, replace the plug.
TESTING
An accurate way to test glow plugs is with an ohmmeter.
Touch one prod to the glow plug's wire connection, and the
other to the body
of the glow plug, as shown. A good glow
plug will have a
1.0 - 1.5 ohm resistance. This method can be
used with the plug in
or out of the engine. You can also use
an ammeter to test the power drain
(8 - 9 amps per plug).
A WARNING: These glow plugs will become very hot
to the touch. Be careful not to bum your fingers when
testing the plugs.
Re-install the plugs in the engine and test them again. The
plugs should get very hot (at the terminal end) within
20 to
25 seconds.
If the plugs don't heat up quickly, check for a
short circuit. When reinstalling the glow plugs, use anti-seize
compound
on the threads.
A WARNING: Do not keep a glow plug on for more
than 30 seconds.
Glow Plug Tightening Torque 7 -11 ft-Ib (1.0 -1.5 m-kg)
TERMINAL END
GLOW PLUG
THE OHMMETER TEST
Engines & Generators
38