FUEL SYSTEM
-
Injection
Pump
FU-55
INS PECT I ON INJECTION P U M P
1 .
2 .
NOTE:
Do not
lauch
t h e
s l i d i n g s u rfaces o f t h e p u m p
plunger and delivery valves.
INSPECT DELIVERY VALVES
(a)
Pull up t h e valve and
close
the
hole al the valve seat
bottom end with your thumb.
When the valve is released. it should sink down
quickly and
Slop
a
t
the
p
os
i
t
ion
where t h e
relief
ring
closes t h e valve
seat hole.
I f defective, replace
the valve
a s a sel
(bl
Close
the hole a t
the
valve seat bottom end
with yOur
t
h
u
m
b
Insert the valve i n l O the valve seat and press
down
with your
finger.
When your
finger i s released, the
valve
should rise
back:
to its original position.
Replace
il defeclive
!c ) Remove your t h u m b from the
valve
seat hole.
The valve should close com pletely by
its
own weig ht.
Replace
If
defective.
NOTE:
Belore using a
new
valve set, wash off the rust
prevention com pound
with
light oil or gasoline.
Then Ie-wash wilh
diesel
fuel and perform the a bove
lests.
INSPECT PUMP PLUNGERS
l a ) T i l t the cyl inder slightly and
p u l l
out
t h e plunger.
(b)
When
released,
t h e plunger
should sink down
smoothly into
t h e
cylinder by i t s
own weig h t .
( c ) R o t a t e the
plunger a n d
r
ep
e
at
the t e s t
a t
various
positions.
If
t h e plunger
sticks
a l
any position, re place
it
a s a set.