Yanmar 4LHA-HTP Operation Manual page 418

Chapter 3 Fuel Injection Equipment
12. Fuel Injection Nozzle
(4) Clean the nozzle seat with cleaning spray.
(5) Clean off the carbon on the tip of nozzle with a piece of
wood.
(6) Clean hole type nozzles with a nozzle cleaning needle.
Nozzle cleaning needle (piano wire)
0.2mm dia. wire, 22mm long x 5 wires
C 1
Part code no.
12-3.2 Nozzle inspection
(1) Inspect for scratches/wear
Inspect oil seals for abnormal scratches or wear and
replace nozzle if the nozzle sliding surface or seat are
scratched or abnormally wom.
(2) Check nozzle sliding
Wash the nozzle and nozzle body in clean diesel oil, and
make sure that when the nozzle is pulled out about half
way from the body, it slides down by itself when releas-
ed.
Rotate the nozzle a little; replace nozzle/nozzle body as
a set if there are some places where it does not slide
smoothly.
(3) Inspecting stop plate (inter-piece)
Check for scratches/wear in seals on both ends, check
for abnormal wear on the surface where it comes in con-
tact with the nozzle; replace if stop plate is excessively
wom.
28210-000010
3-1-61
Nozzle contact surface
Seal surface
NT
Nozzle contact surface wear limit
(4) Inspecting nozzle spring
Replace the nozzle spring if it is extremely bent, or the
surface is scratched or rusted.
(5) Nozzle holder
Check oil seal surface for scratches/wear; replace if
wear is excessive.
12-4 Fuel injection nozzle reassembly
The fuel injection nozzle is reassembled in the opposite
order to disassembly.
(1) Insert the adjusting shims, nozzle spring and nozzle
spring seat in the nozzle holder, mount the stop plate
with the pin, insert the nozzle body/nozzle set and
tighten the nut.
(2) Use the special holder when tightening the nut for the
hole type nozzle as in disassembly.
Nozzle nut tightening torque
Hole type nozzle
4LHA-HTE/HTZA/HTP/HTZP
Nozzle type
P / N
i4LHA Serie
Hole type
mm (in.)
0.1 (0.0039)
N-m(kgf-m)
39.2-44.1 (4-4.5)
140P285 KOT
119172-53050