Yanmar 3JH3E - 6-4 Thermostat inspection; 6-5 Testing the thermostat

Chapter 6 Cooling Water System
_6_.
_T_h_er_m_os_t_at
___________________________
3,4JH3(BXC)E
6-4 Thermostat inspection
Remove the thermostat cover
on
top of the fresh water
pump and take out the thermostat. Clean off scale and
rust and inspect, and replace
if
the characteristics (pertor-
m
an
c
e)
have
changed,
or
if
the
sprfng is
broken,
deformed
ar
corroded.
Thermostat
cover
(fresh
water
oul!et
connection}
~Gasket
Printed in Japan
HINSHI-H8009
..--Thermostat
C)
~-
Fresh
water
pump
body
6-13
6-5
Testing the thermostat
(1) Put the thermostat
in
a Leaker with fresh water, and
heat
it
on an electric stove. The thermostat is function-
ing normally
if
it
starts to open between
75~780'C,
and opens 8mm or more at
90"C
Replace the thermo-
stat
if
it is not functioning normally.
{2) Normally, the thermostat should be inspected every
500 hours of operation, but, lt shoufd
be
inspected
before this
if
the coating temperature rises abnormafly
or white smoke is emitted for a long time after engine
starting.
(3) Replace the thermostat every year or 2000 hours of
operation {whichever comes first}.