How does a mechanic repair a leak in a fuel line is there more than one line.?

Answer 1

AnswerI am a licenced technician, and it all depends on what section of line is leaking, if the lines are steel or plastic, and what the rest of them look like. If a steel fuel line is leaking because it's rusted out, (eg. eastern Canada, northeastern US), chances are that large sections of new line will need to be spliced in; in extreme cases, new line will need to be run from the engine all the way back to the fuel tank. In the case of plastic fuel line, if the line is simply cut or split, it can sometimes be repaired with purpose-built fittings; if not, the complete section of line needs to be replaced. Many vehicles have different size fuel lines; General Motors vehicles, for example, usually run 3/8" line to the engine, 5/16" line for return to the fuel tank, and 1/4" for vapour return. It all depends on the vehicle; if the lines are damaged so badly that a technician can't tell which one is leaking, then they must all be replaced. It does no good to patch a bad section, only to disturb the other ones so they start to leak. I wouldn't recommend fuel lines as a do-it-yourself project.