Yanmar 4LHA-HTP Operation Manual page 457

Chapter 3 Fuel Injection Equipment
4. Adjustment of Fuel Injection Pump and Governor
4-7 A d j u s t m e n t of governor
4-7.1 A d j u s t i n g the fuel limit bolt
(1) Adjust t h e tightness of the fuel limit bolt to bring
the rack p o s i t i o n to the specified value (Ri ) with
the g o v e r n o r control lever all the way down
towards t h e fuel increase position. Keep the pump
at rated r p m N , .
N.
(2) Measure f u e l injection volume at rack position
( R J .
(3) If the injection volume is at the specified value,
tighten the fuel limit bolt lock nut.
4 - 7 2 Adjusting R P M limit bolt
(1) Gradually loosen the governor control lever while
keeping the pump drive condition in the same
condition as when the fuel limit bolt was adjusted,
and adjust the tightness of the R P M limit bolt to
the point where the rack position just exceeds the
f
specified value ( R , ) .
Maximum speed
adjustment bolt
Control lever
Full load position
N , N, N,
Pump (rpm)
(2) Check maximum R P M at no load
Further increase r p m , and make sure that rack
position (Rj = R, — L) corresponding to maximum
rpm at no load is within specified value ( N
No load max. RPM
(Pump RPM)
4-7.3 Adjusting idling
(1) Maintain the pump rpm at specif ied rpm (N3).
Control lever
Idling rpm (Pump RPM)
(2) Measure the injection volume as you lower the
governor control lever to the idling position, and
adjust the position of the control lever with the
idling adjustment bolt to bring it to the specified
value.
Measuring stroke
Idling injection volume
4-7.4 Check the injection volume when starting
(1) Make sure the control rack moves smoothly as
you gradually reduce idling rpm.
(2) Next fix the governor control lever at full load
position with the pump at the specified rpm ( N J .
Make sure that the control rack is in the maximum
position.
Measure the injection volume and check to make
sure it is within the specified value.
F o r models with a fuel limit bolt for starting,
adjust to the specified injection volume with the
fuel limit bolt.
3-2-35
4LHA Serie
) .
2
See separate service data
Idling adjustment bolt
See separate service data
See separate service data