C Yukon 2WD V8-5.7L VIN R (1999)
Fuel Return Line: Description and Operation
Vapor Pipes and Hoses
CAUTION: In order to Reduce the Risk of Fire and Personal Injury:
^
If nylon fuel pipes are nicked, scratched or damaged during installation, Do Not attempt to repair the sections of the nylon fuel pipes.
Replace them.
^
When installing new fuel pipes, Do Not hammer directly on the fuel harness body clips as it may damage the nylon pipes resulting in a
possible fuel leak.
^
Always cover nylon vapor pipes with a wet towel before using a torch near them. Also, never expose the vehicle to temperatures higher
than 115°C (239°F) for more than one hour, or more than 90°C (194°F) for any extended period.
^
Before connecting fuel pipe fittings, always apply a few drops of clean engine oil to the male pipe ends. This will ensure proper
reconnection and prevent a possible fuel leak. (During normal operation, the O-rings located in the female connector will swell and may
prevent proper reconnection if not lubricated.)
The vapor pipe extends from the fuel sender assembly to the charcoal canister. It is made up of nylon pipe and is connected to the fuel sender assembly
and the EVAP canister with the fuel resistant rubber hoses.
