55
GAMMA SERIES ENGINES OpERATORS' hANdbOOk
AdjuSTMENT ANd uSE Of ThE pb puMp
1. Important adjustment of the pump should only be carried out on a special test
bench by trained personnel.
AdjuSTMENT Of STATIC fuEl SupplY
Advanced Angle of Inline pump
1. Determine the mark position when the piston of number 1 cylinder is at TDC
on the compression stroke. The mark should be stamped on both the timing
case cover and the pulley.
2. Remove the high pressure pipe of number 1 cylinder, pull the throttle control
lever to the maximum position of fuel supply, turn the crankshaft clockwise from
the front and set the piston of number 1 cylinder to TDC on the compression
stroke.
3. Turn the crankshaft anti clockwise from the front to an angle of more than 60
degrees then turn back clockwise slowly. Observe for the fuel overflow from
the valve seat, when the fuel level fluctuation just appears it indicates the fuel
supply is beginning at number 1 cylinder. At this point stop turning the crankshaft
and check for a difference between the angle on the timing case cover and the
pulley, thus the fuel supply advanced angle can be determined. At this moment,
if the mark on the pulley is ahead of that on the timing case cover it indicates
that the fuel supply is in advance (and vice versa).
4. If the fuel supply advance angle fails to meet the requirement, loosen the nut
on the pump bracket and the flange at the side of the pump and adjust with the
kidney hole on the flange. When moving the pump body close to the cylinder
block it can increase the fuel supply advance angle (or vice versa).
5. The periphery of the flange on the pump body to be turned for 1 mm of arc
length, the fuel supply advance angle can increase or decrease by 1 degree
or crankshaft rotation angle.
6. After the fuel pump supply advanced angle has been set, the nuts on the flange
at the side of the pump and the screws on the pump bracket should be tightened
to the correct torque.
7. Repeat the third step of the operation and check.
Note:
The arc length opposite to 1degree of rotation angle of the crankshaft = πD/360 (mm) where
D is the diameter of the pulley in mm.
Summary of Contents for GW3
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