Wouldn't Start
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RE: Wouldn't Start
I guess everyone here is assuming he has fuel injection not carb.
On fuel injection the pump being in the tank and either fully or partially immersed
in the fuel is not likely to get hot and cause a vaporlock as would some cars that
had the pump mounted on the side of engine block.
Although a defective pump could do what we call cavitation (generate air bubbles internally
which is a type of vapor lock but this is rare)
Also in a properly working F.I. system the entire fuel system has a minimum constant
pressure in it that should not be affected with vapor locking.
When you first turn key on and you hear pump run, it is just bringing the residual pressure
upto a pressure high enough to allow a quick start.
The fuel has to be injected into the manifold / cylinder under a high enough pressure to fully vaporize in time for the compression stroke and subsequent spark firing.
But from the pump to the injectors even after an overnight cool down, some pressure should
still remain in the lines.
If not you have a faulty pressure regulator, leaking injector(s), leaking line or the pump
is not maintaining pressure. all of which will cause a hard start (longer than normal cranking
before a fire up).
And I don't believe his model is liquid cooled so no need to check the cooling system or the thermostat.
full tank plug (electrical harness) on my 01 EGC is on the pump itself, not sure on my 06 haven't looked yet.
My 06 requires I think (have to look it up again to be sure) 55- 62 psi while running.
On fuel injection the pump being in the tank and either fully or partially immersed
in the fuel is not likely to get hot and cause a vaporlock as would some cars that
had the pump mounted on the side of engine block.
Although a defective pump could do what we call cavitation (generate air bubbles internally
which is a type of vapor lock but this is rare)
Also in a properly working F.I. system the entire fuel system has a minimum constant
pressure in it that should not be affected with vapor locking.
When you first turn key on and you hear pump run, it is just bringing the residual pressure
upto a pressure high enough to allow a quick start.
The fuel has to be injected into the manifold / cylinder under a high enough pressure to fully vaporize in time for the compression stroke and subsequent spark firing.
But from the pump to the injectors even after an overnight cool down, some pressure should
still remain in the lines.
If not you have a faulty pressure regulator, leaking injector(s), leaking line or the pump
is not maintaining pressure. all of which will cause a hard start (longer than normal cranking
before a fire up).
And I don't believe his model is liquid cooled so no need to check the cooling system or the thermostat.
full tank plug (electrical harness) on my 01 EGC is on the pump itself, not sure on my 06 haven't looked yet.
My 06 requires I think (have to look it up again to be sure) 55- 62 psi while running.
ORIGINAL: Bryan1724
VAPOR LOCK
Definition: When gasoline overheats and boils inside the carburetor bowl or fuel pump of a hot engine, it ceases to flow. This can cause stalling or hard starting. This is called vapor lock, and it usually happens during hot weather. If a hot engine won't start, all you can do is let it sit and cool off. You should check the cooling system to see if anything is causing the engine to run unusually hot (a bad thermostat or cooling fan, for example). Switching brands of gasoline may also help.
I'd check the plug for the fuel pump where it plugs in to the harness. It's at the back of the fuel tank, where the seat comes up to the tank, in that general area. Well at least on my 99 Roadie that's where it's at.
VAPOR LOCK
Definition: When gasoline overheats and boils inside the carburetor bowl or fuel pump of a hot engine, it ceases to flow. This can cause stalling or hard starting. This is called vapor lock, and it usually happens during hot weather. If a hot engine won't start, all you can do is let it sit and cool off. You should check the cooling system to see if anything is causing the engine to run unusually hot (a bad thermostat or cooling fan, for example). Switching brands of gasoline may also help.
I'd check the plug for the fuel pump where it plugs in to the harness. It's at the back of the fuel tank, where the seat comes up to the tank, in that general area. Well at least on my 99 Roadie that's where it's at.
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