Service Manual

Thermostat Test
If the engine overheats or runs too cool, and a faulty
thermostat is suspected, the thermostat should be
tested.
1. Remove the thermostat.
2. Put the thermostat in a container of water with a
thermometer and heat the water.
Starts to open at: 81
o
C (178
o
F)
7 mm (0.28 in.) full open at 88
o
C (190
o
F)
3. If the thermostat fails to open, only partially opens, or
sticks, it should be replaced.
Figure 37
Engine Page 3 - 32
Rev. B
Reelmaster 335-D/3500-D