Doosan DX60R Shop Manual page 268

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 (2, Figure 108) in the valve
cover (2, Figure 108). 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 (3, Figure 108):
1. Remove the bolts retaining the diaphragm cover (4, Figure
108).
2. Remove the diaphragm cover, spring, diaphragm plate (5,
Figure 108) 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.
Failure of the diaphragm and / or spring will cause the loss of
pressure control and allow an excessive amount of crankcase
fumes to be routed to the intake manifold. This could result in
excessive deposits in the intake system, high engine exhaust
smoke levels, excessive engine oil consumption, and / or
engine run-on due to the burning of the engine oil.
Engine
Page 88
Figure 108
SP001693