2nd Gen Non-Engine/Transmission Weird fuel tank problem?

[Hogan]

I've been having some weird problems lately. I ran out of fuel for the first time the other day and the fuel gauge still said I had a bit left. The low fuel light wasn't even on solid yet. So, I push the truck to the station and fill it up. The weird part is it only took 27. 3gal before it was completely full including the fill tube. My usual fill amount is 26gal and I was able to get 32gal in once. What would cause this to happen, run out of fuel and only take 27gal? Only thing I can think of is a broken or leaking fuel pick-up in the tank and after it gets below a certain level it just starts sucking air. Sound logical?



The other weirdness is when it started dying it also started belching out tons of smoke. Once it was filled back up and restarted it was back to normal. Why would it belch out so much smoke when it was running out of fuel? It also spits out a bit of blue smoke when first started and driven, but goes away when warmed up and only happens at high altitudes, once I drop down to sea level I don't have that problem anymore. I've pretty much resigned myself to "it just does that", but this fuel tank problem has me weirded out. Any ideas?

 

[Extreme1]

Sounds like the line rubbed through on the pick up all right. There was another post on here within the last couple months with the same thing.



You didn't have to re-prime the pump to restart it?

 

[illflem]

You could also have a contaminant like water in your fuel tank, but 8 gallons seems like a lot. The pickup slides on a track so it doesn't pick up fuel from the bottom until the tank nears empty. The pickup may be binding on the track and not reaching bottom. Either way I'd say it's time to drop your tank and take a look.

 

[KBarrett]

Weird Fuel Tank Problem

I had about the same problem as Hogan with my truck(97 2500 4x4). I stopped at a stop sign and she died, added about 3 or 4 gallons of fuel, used air on filler neck and cracked bleeder to get re-primed, truck cranked and ran fine, drove to the nearest fuel stop (about 2 miles) and filled her up, only held 21 gallons... . kinda wierd, a 36 gallon tank. My guage has acted up in the past and has worked right the last year, I thought when the truck died the level sender was acting up again, after only holding 21 gallons I knew this wasn't the problem. I have helped a couple of friends replace their sending units in the past, I remember the slotted slides on the pick-up because on the last one we fixed we filed the burs off on each side of the tube because it looked like it would possibly make the slide stick. Is this my problem? Has anyone else had this problem?

 

[mhenon]

Contaminated fuel?

Contaminates in the fuel sounds like the place to start looking. Instead of dropping the tank, I wonder if you couldn't just drain it out real good first. And maybe fill up using a diesel fuel additive (lubricant). Clean fuel and an additive "might" clear this up in a tankful. Couldn't hurt anything!

Mike

 

[PUMPERDUDE]

I think you're on the right track by looking at the fuel pickup. The module is a real piece of junk if you ask me. When I changed my sending unit I noticed my pick up had been stuck in one position for a looong time. The screws had worn though the tracks. I just put some flat washers on the screws to lock it down and keep it from falling .

I'm not sure why this engine smokes when running out of fuel. I've witnessed this My guess would be as the injection pressure falls, so does the ability to get a clean burn. Maybe one of the gurus could chime in and give the answer.