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Fuel Problems, air leak, lift pump and dropping tank

2K views 6 replies 3 participants last post by  illflem 
#1 ·
I've always had a small air leak in the fuel line since I bought the truck about a year ago. Since I have not pulled anything significant it was only a problem at WOT or climbing a major hill at freeway speeds. In addition, the fuel pressure gauge only read 20lbs at best at idle and would drop to 13lbs WOT when the air becomes an issue. This is a 95 12v 2500, extended cab. BTW, changing the fuel filter made no difference here.

So last week I decided to replace all the original rubber fuel hoses, filter and lift pump. And also bypass the fuel heater.
So here is the problem:
1) New lift pump is not making pressure - 5 lbs is max
2) Still have small air leak (seen in site tube). I believe the air leak is actually at the tank where it draws the fuel.

For the lift pump, I'm going to hook the feed line directly to a jug of fuel. Then I will know if the new LP is bad or if there is restriction in the line somewhere.

If the source of the air leak is at the tank cap or something inside the tank, is there an easy way to test this? What is the best solution for a cure?

Also, any great ideas on how to drop the tank? I've attempted this twice last week. The problem is the front strap. The extended cab has a two piece drive shaft and the front strap is wedged into the mounting bracket for the drive shaft. I can easily unscrew the strap and pull it away from the bolt. But that is all the movement I can manage without removing the drive shaft mounting bracket. Ideas?

Thanks,
Michael
 
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#2 ·
Your LP test sounds good.

I don't know about your '95, but I've dropped fuel tanks on a '96 and '97 (both extended cab)and it was pretty simple. Undo the nuts on the holding the straps up, and take a wedge of some kind and pry the strap from the frame and it should come down. I also took some rope and attached it to the frame went under the tank and then over the frame and had my brothers hold it so it wouldn't fall on me and that way I could disconnect the wiring and hoses, and then let the tank down slowly. the '97 was a 2wd and I had to jack the back tire up and put a block under to get the tank out. you could drive it up onto a block, I did it the way I did because I had a really big air leak and the truck would not start.

I'll try to get pics just to make sure mines the same as yours.
Any more question feel free to ask.
 
#3 ·
Holding the tank as it comes down is not a problem - I use an ATV jack to support it and lower it. Getting that front strap released is a headache. I just found a thread that said I needed to pinch the front strap hard against the tank (away from the drive shaft mount) to get the strap free of the drive shaft mount.

I just ordered a new Draw Straw I. I'm hoping the air leak is limited to that part. Since I am in AZ, fuel lines rusting out is rarely a concern.
 
#5 ·
That top picture shows your strap just inside the bracket. My strap is fully inside that bracket and the strap is wider than the rolled part of the bracket. Thus I have not been able to get the strap out of the bracket.

I'll wait until the new Draw Straw arrives and then attempt to remove that strap with a BIG pry bar. Thanks for the pictures and the input.
 
#6 ·
#7 ·
Since I am in AZ, fuel lines rusting out is rarely a concern.
Rusting isn't a problem in my parts either but what is a problem is the metal line cracking on top of the bell housing where the bolt down tab is welded to it.
Replace both the supply and return lines with quality hose and abandon the entire stock low pressure system.
 
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