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View Full Version : Not enough fuel pressure to FPR


Whizbang
09-21-2008, 09:34 AM
so i have start hunting into why my carb is seeing no fuel. Back checked everything and found that the line running TO the FPR has little pressure / volume. If you hold the hose up, it can barely even flow out. The pump is running, but it seems like i should be getting much more fuel than whats is cranking out.

The pump is a Carter, not sure what model. Is there adjustments on these pumps? There is no restrictions in the system from what i can tell. Purhaps something intake is no longer funcational?

Sterling
09-21-2008, 10:44 AM
Is your filter set up correctly, before the fuel pump?
A fuel pump can be destroyed by rust chips.

Have you tested at the pump to rule out blockage between the pump and regulator/carb?
And is your tank breathing correctly? (Do you get a strong "whoosh" when you open the gas cap?)

Whizbang
09-21-2008, 10:56 AM
the filter is before the pump. The pump WAS a known working used pump but i wont rule out that its been damaged before i installed it. Car has not run on the pump. The vent lines are open to air. I didnt have any "whoosh" when i opened the gas cap.

I am going to have to get under the car and pull the line after the pump and see how the flow is.

Rogue_Wulff
09-22-2008, 09:08 AM
Deffinately check for flow at the pump. If the pump isn't putting out much, it could be a restriction in the line coming from the tank. If the car has sat for any length of time, the pickup tube could be clogged. That's always a fun job on S1/S2 cars, due to the lack of a removable assembly.

Whizbang
09-22-2008, 09:25 AM
the thing is, its hard to say whether or not the pump is shot without checking the tank...

maybe i could just get a gas tank, have a tube from it to the pump, the from the pump to another can and see what its flowing

BigTeddy
11-20-2008, 06:00 PM
Main problem with not getting a good reading on the reg's is sometimes he/she run to big of return line on the fuel...which is not allowing the fuel press reg read correctly...In that instance fuel is just flowing to from and back from the tank however it feels with no built up pressure....

On my setup with the racing beat intake mani and holley 600 i don't have a return...there is no need...press reads fine and is set at the desire i want it and the carb will only take what it wants either way...So all in all its a win win situation

BigTeddy
11-20-2008, 06:01 PM
the thing is, its hard to say whether or not the pump is shot without checking the tank...

maybe i could just get a gas tank, have a tube from it to the pump, the from the pump to another can and see what its flowing

Yes that is a good way to check if the pump is working correctly...Also what size return line you have...in most cases a return line is not needed if the reg is set to the correct fuel press...

As mentioned before i myself im not running a return...