Yanmar 3JH4E, Service Manual

Page: 101 / 350

2. Inspection and adjustment
81
(7) Wash turbocharger blower
When engine speed seems sluggish or the
exhaust color poor, the blades of the
turbocharger blower may be dirty. Wash the
blower in the following manner.
1) Prepare blower wash (liquid detergent),
fresh water, and a small pitcher.
Blower wash (4L)
Parts code: 974500-00400
2) Put the clutch in neutral and run the engine at
high speed (2500-3000 min
-1
).
3) Slowly pour approximately 50cc of blower
wash into the inlet hole of the intake silencer
over a period of about 10 seconds.
4) After about 3 minutes, pour in approximately
50cc of fresh water in the same manner over
a period of about 10 seconds.
5) After operating the engine for about 10
minutes, check the boost pressure and power
output. If there is no improvement after
washing the blower, repeat the washing
process several times.
NOTICE:
Do not pour in a large amount of blower wash
at one time (pour it in gradually) as this can
damage the blower blades and get water
hammer in the combustion chamber leading
to accidents.
(8) Clean the exhaust/water mixing elbow.
There are two types of mixing elbows, the L-
type and the U-type. The mixing elbow is
attached to the exhaust manifold. The exhaust
gas is mixed with seawater in the mixing
elbow.
1) Clean dirt and scale out of the air pass and
seawater pass of the mixing elbow.
2) Repair the crack or damage of the mixing
elbow by welding, or replace if necessary.
Note:
Replace the used mixing elbow with new one
periodically every 500 hours or 2 years, even
if any damage is not found.
3) Inspect the gasket and replace if necessary.
Blower wash
Inlet
Turbocharger
Intake silenser
010537-00E
L-type mixing
elbow
Gasket
Seawater
Exhaust manifold
010624-00E