Fuel / Exhaust
4.39
Fuel L in e Air L eak Testing
Fuel lines may develop air leaks causing the PWC to run lean or be hard to start. If you suspect this to be the
case, the following would be suggested areas to check.
All fuel line clamps: Carb rack hose connections; fuel line from carb rack back to fuel pump; fuel pump back to
shut off valve; shut off valve to fuel tank drop tube, then drop tube lines within tank. The return line may also cause
lean conditions to exist regarding inlet needle and seat pop off.
Fuel lines within the fuel tank may become distorted from fuel additives. In this case, lines should be replaced.
1. To check for air leaks in the main fuel line, remove fuel in line from fuel pump and fuel out lines from fuel tank.
Attach a Mity Vact to one end and plug the opposite end. Pressurize the line with 10-14 PSI. The line should
hold this pressure for five minutes. If pressure will not hold, check hose clamps and fuel shut off valve.
2. To verify if the shut off valve is leaking, bypass the valve. If it maintains pressure, the valve is faulty and should
be repaired or replaced. This test should be done on both main fuel line and reserve line, switching the shut off
valve accordingly.
3. To check for air leaks from the fuel pump through the carb rack, remove the fuel line from the fuel pump out
line, and remove the return line from the fuel tank.
4. Attach one end of the line and install the Mity Vact on the other end. Apply 8 to 9 PSI to the line. It should
maintain that pressure for five minutes. If not, check hose clamps and inspect lines for damage. If after
checking lines and clamps no leaks are found, carbs should be taken apart and inspected.
To Next Page
Loading...
Need help?
General
