Engine Maintenance
116
5. Place the new trochoid feed pump on the
injection pump.
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 TK486V25 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.
NOTE: Do not pull the plunger out of a cold
start device because that will damage it.
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
O
N
key to turn the unit on.
2. Press the
G
AUGES
key before the engine starts
(to enter the Gauges Menu) 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.
1.
Plunger (Extended)
Figure 192: Cold Start Device
1
1.
Banjo Bolt
2.
Engine Coolant Fitting
3.
Coolant Hoses to Cold Start Device
Figure 193: Remove Engine Coolant Fitting
1
2
3
