Yanmar 4TNE98, Service Manual

Page: 63 / 246

4TNV98 & 4TNE98 Diesel Engine Section 2. Periodic Maintenance 61
Every 1500 Hours of Operation
Perform the following maintenance every 1500
hours of operation.
• Inspect, Clean and Test Fuel Injectors
• Inspect Crankcase Breather System
Inspect, Clean and Test Fuel Injectors
WARNING
HIGH-PRESSURE HAZARD!
Avoid skin contact with the high-pressure
diesel fuel spray caused by a fuel system leak
such as a broken fuel injection line. High-
pressure fuel can penetrate your skin and result
in serious injury. If you are exposed to high-
pressure fuel spray, obtain prompt medical
treatment.
NEVER check for a fuel leak with your hands.
ALWAYS use a piece of wood or cardboard.
Have your authorized Yanmar industrial engine
dealer or distributor repair the damage.
Failure to comply could result in death or
serious injury.
Proper operation of the fuel injectors is required to
obtain the optimum injection pattern for full engine
performance. The EPA / ARB requires that the fuel
injectors are inspected, cleaned and tested every
1500 hours. See Testing of Fuel Injectors on page
164.
This procedure is considered normal maintenance
and is performed at the owner’s expense. This
procedure is not covered by the Yanmar Limited
Warranty.
Inspect Crankcase Breather System
Proper operation of the crankcase breather system
is required to maintain the emission requirements of
the engine. The EPA / ARB requires that the
crankcase breather system is inspected every 1500
hours.
There are three different crankcase breather
systems used on the TNV engines. Only the non-
turbo TNV engines crankcase breather system
requires periodic maintenance.
The non-turbo TNV engines use a crankcase
breather system that has a spring-backed
diaphragm
(Figure 5-19, (1)) in the valve cover
(Figure 5-19, (2)) . When the crankcase pressure
reaches a predetermined value, the diaphragm
opens a passage that allows crankcase fumes to be
routed to the intake manifold.
To inspect the diaphragm and spring
(Figure 5-19,
(3)) :
1. Remove the bolts retaining the diaphragm cover
(Figure 5-19, (4)).
Figure 5-19
2. Remove the diaphragm cover, spring, diaphragm
plate (Figure 5-19, (5)) and diaphragm.
3. Inspect the diaphragm for tears. Inspect the
spring for distortion. Replace components if
necessary.
4. Reinstall the diaphragm, diaphragm plate, spring
and diaphragm cover. Tighten the diaphragm
bolts to specified torque.