94 fuel tank lines
 

Hey all, So I recently picked up a 94 f350 with the 7.3 turbo idi and a 5 spd. This has been something that I've wanted for a while. Mainly to tow my built 2000 jeep cherokee.

I have to replace the leaking fuel tanks before I can pass emissions and register this thing. I have a temporary plate so i can do this, which gives me until next monday.

Tonight I started my tank replacement which I figured was simple enough. I bought some spectra steel tanks and new straps. I got the rear tank down and out and there is some trouble with the fuel lines.

The line between the high pressure line and the sending unit was replaced with a piece of rubber fuel hose. There is a piece of old rusted line left in the end of the high pressure line (that the rubber fuel line was spliced in by) and i cant get it out for the life of me. Its all full of gunk and rusty stuff. I've tried to clean it out with a pick but i cant get it out. The metal take offs on the sending unit side have obviously been cut, i suppose to accept the rubber fuel line.

It seems that the only way to fix this would be to replace the sending unit and the entire high pressure line that runs the length of the frame. I don't really want to do that unless its completely necessary. So my question is, is it safe to cut out the braided steel/rubber coated hose at the metal hard line and run rubber fuel hose all the way to the sending unit? I thought that these were relatively low pressure systems, please correct me if im wrong. My main reason for wanting to solve my problem this way is that the hard line just converts back to rubber line before the pump.

Also, the factory tank straps had rubber between them and the tank, the replacements don't. should I put something in there? what?

Also also, just yesterday when i turn the key to the on position and am waiting to start, i started to get a clicking noise and the little battery light goes on and off. My brother said he thought it was coming from the glow plug relay, a black unit on the left side of the block near the firewall. Is that what that is? or what my problem is?


Thanks in advance!

A picture would help out, But there is no high pressure fuel lines on a IDI fuel pump is on the engine,If I understand what your saying is a rubber line inside the tank? If so its because they have a thing called a shower head and they rot and fall off so every one just adds a piece of fuel line to get all the fuel from the tank.

Yes the clicking is the glow relay when it starts clicking it ready to start the truck.

You can go to Lowes and in the roofing section there is a roll of window and door sealer its approx 5" wide and foil on one side and sticky tar on the other works great.

No all of this is outside the tank. my shower head looks to be in great shape.
There is the metal line that runs the lenght of the frame which then turns into a steel braided/rubber coated line that goes from the frame to the sending unit(maybe, or whatever the real name for the shower head is). on mine that steel braided line( which i called high pressure because its steel braided, but like i said i thought they were low pressure systems) was connected to the sending unit with a piece of rubber fuel hose. This was done i think when the metal line between that line and the sender rusted through, so they spliced in a rubber hose which attached to a piece of the metal line left inside the fitting of the braided line.

I want to cut that braided line out completely and just run rubber hose from the metal line on the frame all the way to the sender. I assume it would be fine since its low pressure.

I could get pictures but not until after work and by then I will just be doing it.

The rubber hose should be fine.
My '88 has metal lines for part of the frame, then converts to plastic (nylon?) before the tank selector valve, then runs plastic from the valve to both tanks.
Several people have replaced the plastic with rubber line, just make sure you use diesel rated fuel line. You can just cut the hard line before it converts to the steel braided section and run rubber from there.

right now im trying to bleed the injectors, i just got my 5/8 line wrench back so im hoping that i will be about to get more lossened then the 3 i have cracked opened. but off those three, one was spurting out fuel (second back pass side), the front pass side bubbled, and the drivers front let out a few bubbles. when i tighted dont the one that spurted out fuel it was still letting out some bubbles, does that mean they need knew o rings?

If your talking about the hard lines be careful them puppies are spendy and hard to find! The Diesel store sells them when in stock,no there is no O ring on the line it has a special flair you really only need to crack open one most of the time once running the fuel pressure will force the rest of the air out.

You really should change out the return lines, caps and O rings,One of the best investments on these engines to prevent air intrusion.

Ive been told that, just open one. I cant get the truck started, its gotten close but nothing.

There isnt any fuel coming out of the shrader valve either, just little spurts of air, this bothers me the most right now

The fuel pump MUST go in straight there is a very small margin of error on the drive arm, They can very easily miss the cam eccentric if you take a mirror and turn the engine until the eccentric is out of the way so there is little pressure on the pump arm it helps.

How much fuel in the tank?
.......You should have 10 gallons minim.

Replace the lift pump...

WITH glow plugs disconnected! Will keep it from sucking batteries dry so fast....

Fill fuel filter first,Crank 15 seconds...push shrader valve....crank 15 seconds push valve...when you get pressure then crack a line...

never touched the fuel pumps. 10 gal minimum, thats more then half full. I just replaced both tanks i have about 6-7 in rear and 6 in front/side

Im charging the batteries. I have closed the lines already, hopefully i can get some pressure to the shrader and go from there.

That should be fine then,One reason you want a half tank is the return line should be under the fuel level, But Id say your lift pump is bad it should have fuel in a matter of seconds of cranking...Filling the filter will help,If it doesnt the pump is bad, Or you have a blockage at the duel tank plunger, Or a line has a hole you didnt catch.

These are all things that ive been thinking about. I feel like it must be my lift pump. i just got back from a picnic after leaving the batteries to charge. It sputtered to life for a few seconds and then on the next crank in was running for a good 20 seconds and then died again. which made my hopes go way up but now another 3 cranks latter and it hasn't done it again.

if there was a hole in the line even a pine hole i would assume it would drip even if very slowly. especially when sitting all day.

So im thinking a clogged line might be my problem. i took off the filter and it was half full. but the truck just made a 90 miles drive back to my house 2 weeks ago. im reading up on lift pumps too, they dont seem to be too expensive so maybe replacing it will be good idea while in the process of finding the clog.

20.00 bucks or so, guy I bought my donor truck from spent 1200.00 trying to it to run not including what he bought it for...I bought it for 500.00 and tossed in a lift pump fired right up! Its the simple things that can bite.

Im picking one up tonight then. Ill replace some of the out fuel lines while im at it i guess.

You stated you have a '94 IDI turbo with 5 speed. Unless a previous owner removed the auto E4OD and installed a 5 speed your truck has the 7.3 L powerstroke with 5 speed. No IDI came with manual transmissions. Also the IDI powered trucks have the manual fuel pump on the front passenger side of the engine block. The power stroke powered trucks have the fuel pumps in the tank. I have a '94 F350 IDI Factory Turbo CC Dually 2x4 Centurion Pacifica. My tanks only have a fuel level sending unit and shower head. The lines are a hard plastic pipe that changes over to steel braided rubber with a special Ford connection at the both ends. It would be best not use clamps as a leak would be air intrusion into the lines and could cause hard starts down the road.