Bought a 94 crew cab dually a few weeks back and upon purchase the guy said that the float in the front tank does not work which gives an inaccurate reading on that tank. I have only been running on the back tank so haven't really looked into it. Is there a way I can tell if that's whats wrong? I'm not even too sure how much fuel is in it or what steps to take first to trouble shoot it. Any help would be nice. Thanks

Brandon

 

Both my front and back tanks had broken pick-up tubes so anytime it got to 1/4 tank (under 1/2 tank on hills), it would stall out or surge or act weird as it ran out of fuel.

You should drop both of them and replace pick-up tubes with rubber line or similar because if they aren't broke yet they will be...

also look for or replace any bad hose where they connect to tank as mine had a air leak at the return line fitting also.

as for the sending units they are expensive to replace I think...

 

Never dropped a tank before. Do you have any tips that make the job easier or that I would need to know before starting?

 

the front tank was pretty easy after I first cleaned the bolts/threads with a wire brush and some WD-40/PB Blaster
my bolts, etc were very rusty and it was a b*&^% to get them off.

my bolts were 15mm nuts and 13mm bolts...
after getting the bolts loose for the straps it's easy from there

put a jack or use two jacks to lower tank if it has alot of fuel in it

lower enough to disconnect the fuel lines and sending unit wires then lower all the way
also disconnect the filler hose

it's a good time to clean the tanks really well also- look especially for any black sludge coating the tank walls...my tanks were full of sludge, etc

it's also a good time to make sure all the connections on the selector valve are clean and working, etc as it's hard to get to when the tank is in place.

make sure you put the back tank back on first as the front tank, once reinstalled tends to block access to the lines and valve...

the back tank may not come down as easy as mine would not clear the stupid exhaust pipe hanger and I had to bend it out of the way and rebend it.

and the back tank barely fits and is hard to get out due to having flanges on each side.

when putting it all back together make sure every clamp is tight as any air-leak will cause huge problems...

be very careful once you take off the lock ring for the sending unit
once you remove the sending unit the edges of the hole are razor f&*^%$ sharp!!
it will literally cut right through you if you stick your arm in there to clean it!

make sure to sand or file the opening edges!
I cut the s*&^ out of my hand just brushing against it!

replace pick-up tubes with rubber hose, make sure to cut a large V in the opening of the hose so it can't suction itself to tank floor

try to measure pick-up hose so it just clears the tank floor

 

Yeah, I just had to remove my rear tank this weekend and as i had never done it before and while my mechanical experience is ever growing I'm still very much an amateur. With that said make sure to buy a new gasket and lock ring for the tank(s) you need to remove, mine was rusted and had to be replaced.

x2 on everything he said his procedures and steps were very accurate, one thing that he didn't mention that held me up was there are 3 "lines" running to each tank your return line the line that pulls fuel from the tank and the electrical line that attaches to your bobber. That electrical line just pulls straight up to be removed. The 2 fuel lines have plastic clips that clip around the head of the line I'm guessing they are suppose to make the connection tighter anyways there is a tab on those clips just get a Flathead and pull them off (don't lose them).

It was very easy to remove the existing fuel from the tank. What I did was when I went to buy the 3/8's inch rubber hose for my pickup tube fix i just bought like 5 feet of it stuffed one end deep into the tank and the other into something that can hold at least the same amount and did the old WV siphon and just sucked it until i tasted the fumes (i say that, but really i damn near swallowed the ****) and stuffed it into the container i was using to offload the fuel.

Apart from that your not going to find anymore detailed info for removing these tanks than what he posted.

Edit: Just as an FYI, I did this by myself and i have very little mechanical ability it took me about 5hours from start to finish, so dont think you cant do it.( I couldve def used another person when putting the tank back on)

 

Right on tje2015!
I forgot to mention the clips...what's bad is a pack of 5 of those fuel line clips is $6 here in Va at Advanced Auto!!?
WTF?

So, if possible try not to damage them when removing them with a screwdriver....

On my front tank someone had already cut-off the line ends so I just replaced the small clamps with new ones and some 3/8id line.

Just make sure every hose, etc is airtight or you're gonna have issues with it running.

I knocked a small hole in my back tank prying on it with a bar, like a village idiot
its about a 1/4 inch hole and it's near the top of the tank so maybe I can patch/plug it....

if you're doing it by yourself use a jack and jack stands OR I read somewhere on here a member used those ratcheting straps to raise/lower them which is probably easier

I wish I had the time to make a proper pick-up tube with screen, etc...

Did any of your tanks (any of you) have any sludge, grime, or black flaky stuff coating the tanks??

My tanks had no rust but lots of sludge, sand, gravel, metal shavings, and sludge in them....
I assume the metal shavings are probably from my IP or something...eek!

 

Thanks for the great descriptions. I think I'm ready to take on this job when I get some spare time.

 

When I pulled my tank it was crystal clear on the inside I could however tell there was sludge in the tanks. And linus I'm in virginia too? Where are you located?

 

I have the same problem with my front tank, what is the approx. size (dia and length) of the rubber line needed? my rear tank isn't giving any problem...yet lol

 

Hey tje2015!
Orange, Va

3/8" inside diameter for tank to engine line
5/16" inside diameter for return line

When you get the time/urge you should probably do the rear tank too as the stock pick-up tube is junk and will break off sooner or later...

Read up on Asphatenes when you get a chance

Fuel School: Asphaltene's and Plugged Fuel Filters

Diesel Fuel Facts