Technical data

ADJUSTMENTS
(1) Adjustment of Valve Clearance
Pull off the air breather from the rocker cover, and then
loosen off rocker cover bolts. Adjust the valve
clearance at top dead center of compression stroke
(cold) of each cylinder. Prior to the measurement of the
valve clearance, re-tighten cylinder head bolts to
specified torque. Give care to exact alignment of the
timing mark of the gear case with that on the crankshaft
pulley; if not, the valve may be hushed up by the
piston, depending on the position of the cam lobe.
(2) Adjustment of Injection Timing
Incorrect fuel injection timing will result in hard engine
starting and poor engine performance. Adjust the injection timing in the following manner. First
remove No. 1 delivery valve holder. Pull off the delivery valve and spring. Install the delivery
valve holder only. Subsequently turn the crankshaft, and find an instant when the fuel flowing
out of the outlet port of the holder stops. This instant is the injection timing to be obtained. The
injection timing differs with engine specifications; be sure to adjust the timing to specification.
(Align with the timing mark on the crankshaft pulley.)
Marine engines 230 BTDC
Generator sets 190 BTDC
Angles between timing marks on the crankshaft
pulley are illustrated at right.
When the specified injection timing cannot be
obtained, adjust by increasing or decreasing the thickness of
the injection pump mounting shim. Changing the shim
thickness by 0.l mm changes the injection timing by about 1
degree. If this adjustment cannot be made, adjust by the following method without removing the delivery
valve and spring. First disconnect No. 1 injection pipe at the nozzle holder side. Then, using a wrench on
the crankshaft pulley nut, gradually turn the nut. The instant the fuel in the forward end of the pipe
expands is the injection timing. In this case, the injection timing takes place about 1 degree later than the
specified.