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Injection pump governor
The governor adjuster device (1) is placed in the gov-
ernor housing end and consists of an electromagnet that
works directly against the injection pump control rod.
(2A) and (2B) function as position sensors for the con-
trol rod. They enable the control unit to decide at every
moment if current to the adjuster device has to be in-
creased or decreased. (3) is the main speed sensor in the
system and it works against the toothed gear on the
pump camshaft.
Adjusting
The clearance between the stop lever and the stop cyl-
inder push rod, when the stop cylinder is activated,
should be, on the THD103 engine, 0.3–0.6 mm. Ad-
justment is made with the push rod adjuster screw.
Adjustment is made on the engine by adjusting the po-
sition of the stop cylinder with the attachment adjuster
nuts. Remove the push rod from the stop lever. Turn
the top lever to the stop position and pull the stop cyl-
inder push rod out to the end position. Adjust the posi-
tion of the stop cylinder to get a clearance of 1–2 mm
between the push rod and the lever.
Compressed-air cylinder for
emergency stop
For safety reasons, there is a compressed-air cylinder
for emergency engine switch-off. It is placed on the in-
jection pump.
Normally the engine shuts down when the feed voltage
to the EDC control unit is broken by turning the start
switch to position “0”. The compressed-air cylinder
then turns the governor stop lever to the stop position.
The chief function of the compressed-air cylinder is,
nevertheless, to act as an emergency stop in order to
eliminate negative results from involuntary throttling
caused by cable failure between the control unit and the
injection pump. A signal is sent out from the EDC con-
trol unit to cut out voltage to the compressed-air cylin-
der solenoid valve and this activates the compressed-air
cylinder to engage emergency stop.
In some cases there may also be a stop control in the
engine compartment or next to the battery box. This
control must be pushed in before the engine can be re-
started.