Ford Transit 2002 Owner's Manual page 784

4. To install, reverse the removal procedure.
Removal Details
Item 3 : Thermostat cover
1. Detach the thermostat housing cover and
position it to one side.
Item 5 : Thermostat O-ring seal
NOTE: Discard the O-ring seal.
Installation Details
Item 5 : Thermostat O-ring seal
NOTE: Install a new O-ring seal.
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