Help!!! Fuel Problem with 74 2500m

[Popzak]

I developed a leak about a week ago,just where the fuel line goes into the tank.After raising the fuel tank enough on the the side to get to the line,I replaced it with new fuel line{rubber) cut off some dried out looking line going toward fuel pump and joined it together wth metal fuel line and hose clamps...
Being I moved the tank around I figured it was a good idea to place a fuel filter before the carbs.I figured the movement of the fuel tank would have stired up any sediment,rust etc.
Since then I can't get fuel up to the carbs.I ran a compressor throught the line to clear it,tried an electric fuel pump and still nothing...Would appreciate Your Help Eddie Zak

[DavidY]

Is the fuel tank breather line clear? Check this, if it is blocked then you've created an effective vacuum!

davidy

[Popzak]

I ran compreesed air through everything,and still nothing...It's getting air in the line somewhere,There are no fuel leaks....
There's 1 line going into the top of tank to Fuel Filler Cap and a Y going into a canister in rear by tank and I can't see where the other line from canister is going,I know it's toward the front of TVR.What next and Thank You....Eddie

[GAjon]

Have you cable tied the fuel line to the chassis? If they are to tight (you only need to have one zipped a bit tight) fuel won't pass but air will.

[Daftlad]

GAjon said:

Have you cable tied the fuel line to the chassis? If they are to tight (you only need to have one zipped a bit tight) fuel won't pass but air will.

Or high or low points where air could be trapped??

[Popzak]

The Strange Part is I didn't change or move anything,except about a foot of line from fuel tank fitting,and joined it to the other end of fuel line with a piece of metal fuel line and hose clamps.I sucked fuel up to the fuel bowl of filter with a pump and it takes forever and you can see it's pumping large amounts of air,compared to fuel.Soon as it starts it runs the fuel out of the fuel filter and isn't pumping any fuel in.Then I repeat the process.I figured after it ran abit it would clear ant air in the system and pump the fuel up,but it doesn't???????????
I don't have a lift so I can't get under car,I'm going to garage and recheck everything later I Thank You for Your Help Eddie Zak

[DavidY]

Eddie

Take the fuel filter out of the circuit, just join the hoses with a straight piece of pipe, you then should be back to the same circuit as before you started this escapade, but with a replacement fuel line in the leaking section.

Could it be that the fuel filter is leaking, ie you are just sucking air when the car is running (assuming that the system goes tank->filter->pump->carb

Do you have an electic fuel pump or the mechanical one, I'm not that familiar with a 2500 so I don't know what it would have had originally.

davidy

[Popzak]

Hi DavidY...It has a mechanical fuel pump with a handle beneath it to prime the fuel up.It works,but like everywhere else I tried it's mostly air that comes out,I have 6 gallons of gas in Tank,so there is enough fuel.
I syphoned the fuel at different points,includeing before the filter.I get the fuel up after some time,but it takes much too long,and you can see it's mostly air being forced up...I've replaced dozens of fuel tanks,fuel lines,fuel filters,and carbs in my time,but I never ran into anything like this...I'll let you know what happens when I get back from garage today.I'm going to start all over again.There's no fuel leaks or crimped lines and the fuel pump works and 1/2 a tank of gas ?????????????????????

[heightswitch]

Popzak said:

Hi DavidY...It has a mechanical fuel pump with a handle beneath it to prime the fuel up.It works,but like everywhere else I tried it's mostly air that comes out,I have 6 gallons of gas in Tank,so there is enough fuel.
I syphoned the fuel at different points,includeing before the filter.I get the fuel up after some time,but it takes much too long,and you can see it's mostly air being forced up...I've replaced dozens of fuel tanks,fuel lines,fuel filters,and carbs in my time,but I never ran into anything like this...I'll let you know what happens when I get back from garage today.I'm going to start all over again.There's no fuel leaks or crimped lines and the fuel pump works and 1/2 a tank of gas ?????????????????????

Fuel pump Diaphragm sounds Knackered. If fuel is above pickup point in tank and you have purged air from line to the pump then air is being introduced to the system at the pump.

park the car on a hill facing downhill so tank is above fuel pump then see if petrol wil syphon to pump, This may also help car to overcome a slight leak in system at diapragm and start.

Neil.

[Popzak]

Problem Solved I just returned from garage.I took fuel pump off and cleaned it out after I inspected it.It seemed fine other than some sediment I removed with carb cleaner and air compressor.I went through all the fuel lines with air compressor and cleaned out all connections that vent fuel tank.I added more fuel almost filling it.I then syphoned gas up to fuel filter and reconnected lines and cranked Her Up.Never sounded better....
I want to Thank Everyone at PH's for All their Help...You guys are the Best..."Peace" Eddie Zak