Ford Transit 2002 Owner's Manual page 821

Item 6 : Fuel pressure regulator O-ring seal
NOTE: Discard the fuel pressure regulator O-ring seal.
Installation Details
Item 6 : Fuel pressure regulator O-ring seal
CAUTION: Do not use silicone grease to lubricate O-ring seals as it will block the fuel
injectors.
NOTE: Install a new fuel pressure regulator O-ring seal.
Information.
1. Lubricate the fuel pressure regulator O-ring seal
with clean engine oil to aid installation.
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