There are two designs used for attaching the fuel feed line to the Throttle Body Injection assembly.
One design uses a fitting with symmetrical sealing faces and is attached to the fuel meter body with a banjo bolt and two special "O" ring washers. The other design uses a fitting with non-symmetrical sealing faces and attaches using a banjo bolt and two special soft metal washers (see illustration below).
Any time the fuel feed line is disconnected, the washers and sealing faces of the fitting must be inspected. If the mating surfaces of the fitting or washers are scratched or damaged in any manner, they must be replaced with the correct service replacement part. The bolt torque is 29 N.m (21 ft. lbs.) for the fitting with symmetrical sealing faces and 33 N.m (24 ft. lbs.) on feed lines with non-symmetrical sealing faces.
It is important that torque be applied at a slow and constant rate using an accurate needle type torque wrench. Over torquing may result in bolt or throttle body damage and under torquing may result in a leak.
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