Fuel Pump Problems.

[CobraSix]

I have a few problems and I'm wondering if they are fuel pump related.

1) Should my fuel pump hold fuel in the line from the fuel pump to the carb after that ca is turned off? When I pulled my fuel lines this morning to do some work, there was no fuel in the line from the pump to the carbs. That doesn't seem right to me. I'm thinking my new fuel pump may be leaking as well as my old one.

2) What PSI should my fuel system be running? I'm going to do a check this afternoon, I'm wondering if I'm getting enough fuel and maybe that is causing my lean condition.

3) Similar to #1, fuel my fuel pump be able to hold fuel from the tank to the fuel pump when the car is off?

Slade

 

[MustangSix]

On new cars with EFI, there is always several PSI of residual pressure in the fuel rail. This is necessary for the car to be able to start immediately.

On cars with carbs, you don't necessarily need this. The fuel bowl in the carb has enough gas to start and run the car for a couple of minutes. It's not unusual for the line itself to go "dry" after being parked overnight, but the valves should hold some fuel to prevent a total drainback.

The fuel pump creates a lot of suction and pressure. Within just a few strokes it should be pumping fuel to your carb. Normal pressure is between 4-7psi.

 

[CobraSix]

The car has no problems starting, just it drains down completely so I'm wondering if the fuel in my oil pan is caused by my new fuel pump leaking too. I'll drain that oil and check to see if it was my carb float leaking and report back tomorrow I guess

Slade

 

[Anonymous]

Slade, if it was gas leaking from your carb, you shouldn't see this as a rise in your engine oil. The carb doesn't hold enough oil to do this. If you are seeing a rise in your engine oil level due to added gasoline, 99.999% of the time it is a leak in the gasket of your fuel pump.