So finally getting around to fixing a major air intrusion problem. Hooked up some clear line between the lift pump and the filter and lots of air bubbles even moments of more air then fuel. I have already replace the Nylon line from the tanks to the Tank selector valve with rubber, replaced the valve and PO removed the factory water separator.

Looking at the steel line running from the old water separator to the lift pump it looks like this may be my problem. I am going to replace the line from the new selector valve all the way to the lift pump, so here is the question....

Rubber seems the easiest but to get the injector line i have read i need looks the most expensive.

I am not that experienced in bending steel line so may be an adventure to get steel line and try to replace the factory stuff.

Not sure about the Nylon line, looks like i wold have to rig something to attach to lift pump (rigging is a strong suite of mine with years of practice)...

any advice of past experiences before i tackle this?

 

it sounds like you are sucking air into the lift pump.
what i would do is disconnect fuel line into the lift pump and run it off a portable fuel source.
no bubbles? then start moving back towards the tank looking for where the air is getting into the system. you may just find the lines are good and the lift pump is bad.

 

Thanks TJC...I replaced the Lift Pump about a year ago (should have mentioned that), thought this was the issue when i first bought truck it started to loose power and die if i let foot of pedal...but that doesn't mean it is not the problem...i will check that before i start tearing lines out..


Do you have a preference in type of line? I have seen guys do all three just looking to hear any horror stories to stay away from.

 

Love the shirt by the way

 

i like to replace with what came with it.
my 7 litre got plastic lines, the falcon and 88 got steel.

 

Theoretically, the nylon lines should last the life of the truck and then some. They absolutely will not rust and have some flex to them. The plastic connectors at the tank/selector valve ends of the lines could crack or break. Also, there are o-rings inside the connectors that could break down and let air in (and fuel out). Downside is they could melt if they got too hot, or get crushed (but fuel lines shouldn't be anywhere they could get crushed...)

Metal lines are rigid and resistant to higher temperatures. My guess is the factory went plastic from the tanks for the pluses listed above, but metal under the engine crossmember to keep the exhaust from being an issue. Metal will last a long time, unless you live somewhere rust is a problem, or you get water in your fuel.

Rubber is cheap, but flexible. Its used only where lots of flex might be needed, like between the hard line and the fuel pump (engine vibrating....) It breaks down much faster than metal or plastic, and could collapse if thin hose is used and there is great suction on the line (probably not an issue on our trucks).

I second Tom's recommendation to start at the fuel pump, drop a section of rubber line into a container with some diesel and see what happens. (a gallon jug might just be enough to work for the test?) If that works fine, start looking at the lines. The metal section would likely be the first to fail.

 

thanks for the feedback guys. Bypassed the steel line going to the pump last night and could not get the pump to pull fuel through (inserted a small section of clear line). Going to try directly into a can tonight to see if that works. If not i am going to look at getting a new pump which is crazy because like i said it is less than a year old. Wonder if i did something wrong installing it....seemed pretty straight foward

 

Aftermarket replacement lift pumps have a horrible reputation. That could very well be your problem even if it is only a year old. You don't still happen to have your old pump lying around to try?

 

Either that or crappy Chinese parts.........what brand of lift pump?

One mod you might research is an electric pump... lots of guys on here are big fans of them, myself included. Much easier priming after filter changes, easier starting (depending) and just all around better IMO.

A Facet/ Carrier electric fuel pump is what you want....

How to replace your mechanical fuel pump with a Facet Duralift electric fuel pump

Edit: the man beat me to it LOL

 

So i don't have the old pump....the current pump is an Airtek from Napa...Any suggestions on an aftermarket one? I have thought about the e-pump just not that hard it hurts...

O'riellys-Precision
Advanced/Rock Auto-Delphi
Auto Zone-Spectra


EDIT: Going to continue to test but wanted to get ahead of it and ended up ordering a new Carter pump from Amazon....will attach it this weekend

 

If it is a mechanical pump age is no determining factor I have had them go out in two months but on the plus side gotta love a lifetime warranty(and mine is an airtex also just from advance)

 

ive installed a bran new napa pump, and it only pumped about 1-2 psi.

do an electric pump.

if you have an upgraded injection system, i suggest a Holley black pump with a regulator.

on a stock IP, a holley red pump is perfect.

 

facet duralift electric pump. the others just don't last.

 

my facet pump lasted 2 months. i never went back.

 

First failure that fast I've ever heard of. There are a LOT of those pumps on these trucks, mine included, going strong for years. Did you use a relay to power it? I have read on this and other sites of the Holley pumps failing in short time.