Service Manual

Delivery Valve Operation (Fig. 45)
The delivery valve serves two functions. First, the valve
op
ens to deliver fuel to the delivery pipe when the
pressure generated by the stroke of the plunger within
the barrel is sufficiently high. The pressure must be high
enough to cause the injector nozzle to open. Second,
after injection into the cylinder the Delivery Valve closes,
reducing the pressure within the delivery pipe to nearly
zero while preventing fuel from flowing from the tube.
Figure 45
Inter-Cylinder Injection Control (Fig. 46)
The amount of fuel delivered to each of the three cylin-
de
rs is adjusted by means of adjusting plates. These
plates function as a cam to position the plunger barrel
within the pump housing.
IMPORTANT: Do not remove the Adjusting Plates
from
the pump housing. If removed, re-calibration
by a diesel shop will be necessary.
If it is necessary to remove the plates, carefully scribe
th
e plate and pump body to allow for exact, correct
reassembly.
Figure 46
Fuel System Service Page 4 - 40 Groundsmaster
®
300 Series