Installation - Mercury MerCruiser D2.8L D-Tronic Service Manual

SERVICE MANUAL NUMBER 22
2. Observe the preceding precautions and place thermostat in container of water. Water
must cover thermostat. Suspend a thermometer in the water. Do NOT allow
thermometer to touch the bottom of the pan.
3. Heat water and observe thermostat pin.
4. Pin must begin to extend (push up) as shown, when water temperature reaches 90
degrees C (195 degrees F.). At 100 degrees C (212 degrees F.) pin should be extended
approximately 5-7 mm (3/16 - 5/16 in.) more than when it was cold.
NOTE: Thermostat shown removed from test water for visual clarity. Do NOT handle until
cool.
5. If pin does not extend (push out), thermostat is faulty and must be replaced.

Installation

1. Coat threads of hex head plug with Loctite Pipe Sealant with Teflon.
2. Install thermostat, spring, new O-ring, and plug with new sealing washer into thermostat
housing bore of adapter. Tighten plug securely.
90-860074--1 FEBRUARY 2002
a - Thermostat Pin (Extended)
f
a - Thermostat
b - Spring
c - O-ring Seal
d - Sealing Washer
e - Hex Head Plug
f - Adapter / Oil Thermostat
a
d
c
b
a
ENGINE MECHANICAL
71084
e
75528
Page 3A-93