Air In Fuel Line? Electric or New Mechanical Pump Needed?

[darrin75]

I seem to get air in the fuel filter and after the cars sits for a few days.  the fuel in the filter is gone. i assume back to the tank.  This indicates a leak somewhere correct?

[Just 6T9 CHGR]

I would say not.  A mechanical pump does not hold psi in the line like a newer car with an electric pump

[Rocky]

Do electric pumps really keep pressure?  I thought that it was because they start before you kick the starter over. 

[Just 6T9 CHGR]

Try and change a fuel filter on a fuel injected car that has 60psi of working pressure & tell me if it holds pressure in the line..... DAMHIK

[darrin75]

It just seems after I run the car a bit the fuel filter is low or dry.  New mech pump you think?  Or electric Pump?  Does the filter need to be full always?

[Ghoste]

Mine does that too.  Modern fuels have a lower flashpoint or something I think.  At least it seems to be a bigger problem for me when the car is run with pump gas than when it gets a tank of racing fuel.  Does the car seem like it is running lean or starving for fuel under driving conditions?  Do you know what the fuel pressure is?

[darrin75]

i don't know what the pressure is, i could try check that.  i really think the problem is the pump, although i would hate to by a new pump, and no fixy.  Any more thoughts

[darrin75]

by the way it seems like its always starving for fuel.  Its like the carb is sucking the filter dry, and the pump can not keep up.

[Ghoste]

Does it seem like it's starved for fuel though?  I'm not so sure you have a problem.  I'm not sure you don't, but...

[darrin75]

yep its starving

[Ghoste]

Split in a fuel line anywhere that is allowing it to draw air?  I'd get a pressure guage on that pump and find out what the output is.  You might also want to run a volume test on it.

[darrin75]

I have checked the lines, no leak.  Thanks for the tips..

[firefighter3931]

I seem to get air in the fuel filter and after the cars sits for a few days.  the fuel in the filter is gone. i assume back to the tank.  This indicates a leak somewhere correct?

It's normal to have an airspace in the fuel filter....it should never be completely full. Check your float levels if it feels like it's starving for fuel.



Ron

[darrin75]

yeah but some times its empty, i know thats no right?

[Ghoste]

Heat will do it.  I've watched the fuel literally boil out of the filter after shutting the car down when it's hot.

[Chryco Psycho]

is your fuel pump push rod worn ? is it a big block ?
possibly the sock in the fuek tank is clogged or the pump is not cycling enough to feed the engine properly