Yanmar 4JH2E Service Manual page 89

Chapter 3 Fuel Injection Equipment
4. Adju~tment of Fuel Injection Pump and Governor
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(5) Check control rack stroke
Make svre the rack position is at 11.5"" 12.5mm (0.4527
"" 0.4921 in.) on the indicator scale when the governor
control lever is set at the maximum operating position.
If it is not at this value, change the link connecting the
governor and control rack to adjust it.
NOTE: Links are availabe in Imm (0.0394in.) increments.
(6) Remove the plug in the oil fill hole on the top of the
governor case, and fill the pump with about 200cc of
pump oil or engine oil.
(7) Complete fuel oil piping and operate the pump tester to
purge the line of air.
(8) Set the pressure of oil fed from the pump tester to the
injection pump at 0.2 - 0.3kg/cm
2
(2.84- 4.26 ln/in.
2 ).
4·2 Adjustment of top clearance
Adjust the top clearance (the clearance between the top
of plunger and the top of barrel with the cam at top dead
center) of each cylinder plunger to bring it to the
specified value by changing the thickness of the shims.
Top clearance
_j_
Plunger barrel
Plunger
mm(in)
Top clearance
0.95-1.05 (0.0374-0.0413)
Pre-stroke
2.5 (0.0984)
Standard shim thickness
1.2 (0.0472)
3-24
Relation between top clearance, standard shim thickness
and pre-stroke.
Adjusting shim thickness
Part Code No.
1.0 (0.0394)
1.2 (0.0472)
1.3 (0.0512)
1.4 (0.0551)
1.5 (0.0591)
1.6 (0.0630)
mm (In.)
129155-51600
(1) Place the top clearance gauge on a level surface and
set the gauge to zero.
(2) Remove the injection pump delivery retainer, take out
the delivery valve assembly, insert the top clearance
gauge and tighten by hand.
~
1
LJ\lo
(3) Turn the camshaft, and bring the cam to the top dead
center while watching the gauge needle.
Printed in Japan
AOAJ029-9002