48
TK 56433-5-MM-EN
6. Install and tighten four hex head screws that attach
the trochoid feed pump to the injection pump.
Torque the hex head screws to 6 to 7 ft-lb (8 to 10
N•m).
Cold Start Device
The TK486V25X engine has a cold start device located
on the fuel injection pump. The cold start device has a
plunger that retracts at engine coolant temperatures
below 41 F (5 C) to advance the injection timing
approximately 2 degrees. The plunger controls the
position of a piston in the injection pump to change the
timing. The plunger is extended and the injection
timing is normal at engine coolant temperatures above
41 F (5 C). Check the operation of the cold start device if
it is difficult to start the engine in cold weather.
N
No
otte
e:: Do not pull the plunger out of a cold start device
because that will damage it.
Figure 44.
Cold Start Device
1.
Plunger (Extended)
Checking Cold Start Device Operation
Use the following procedure to check the operation of
the cold start device. The engine coolant temperature
must be below 32 F (0 C) to start the procedure.
1. Press the ON Key to turn the unit on.
2. Enter the Gauges Menu before the engine starts
and check the coolant temperature to make sure it
is below 32 F (0 C).
3. Let the engine start, then check the engine rpm in
the Gauges Menu. The engine rpm should be
approximately 100 rpm higher than normal (see
Specifications).
4. Let the engine run to warm up and use the Gauges
Menu to check the coolant temperature and engine
rpm. When the coolant temperature rises above 41
F (5 C), the engine rpm should drop back to normal.
Replace the cold start device if the engine rpm does
not drop approximately 100 rpm when the engine
warms up.
Cold Start Device Replacement
1. Drain the engine coolant.
2. Remove the banjo bolt that fastens the engine
coolant fitting to the cold start device. Use a backup
wrench on the cold start device if necessary.
Figure 45.
Remove Engine Coolant Fitting
1.
Banjo Bolt
2.
Engine Coolant Fitting
3.
Coolant Hoses to Cold Start Device
3. Remove the cold start device from the injection
pump fitting. Use a backup wrench on the injection
pump fitting if necessary.
Figure 46.
Remove Cold Start Device
1.
Cold Start Device
2.
Injection Pump Fitting
4. Make sure the piston inside the injection pump
fitting is clean.
