My late '99 F350's fuel guage has started to not be accurate.
A little history:When I first bought the truck 5 years ago I noticed immediatly that the guage was slow to go to full when filling the tank.

Then is was slow to come off of full, but was accurate seeming to me in the one time I let it get to about 1/8 tank the low fuel light came on.
The guage always seemed to work that way, I always filled up at the 1/4 mark.

I started using commercialy made B99.9 Bio-Diesel about 6 months ago and noticed that the guage went right to full with no hesitation, but still took well over 200 miles to come off of full.

Well....last night I was nearing the 1/4 mark (so I thought) with about 440 miles on the tank of Bio with 80% of it pulling my car hauler that weighs about 7k with my Mustang in it.

Coming down the interstate I ran out of fuel, once I realized what was happening I shut it down before it quit on its own-my Wife was kind enough to bring me 5 gallons on fuel that I already had in my can, I put it in, cycled the pump about 6 times then started the engine, started right up, had some air in the system, drove gently to the nearest place and filled it up while letting it idle, all air apparently was blead from the system and it ran fine on the way home.

Now: What to do about my guage problem.......wondering it this points to the float unit in the tank or the guage itself??
Any suggestions appreciated guys. Thanks!

 

i would point toward the sending unit. You can always check the guage by grounding the sending unit. I believe it should swing to full when you ground it.

Barney

 

If you haven't done in-tank mods it is possible that your "umbrella" fuel pick-up has failed. This would cause you to "run out of fuel" early. B99 could have accelerated degradation. Mine was in pieces 3 years ago so they do fail.

 

Guys, Thanks for the QUICK replies!
I have seen the mention of the in-tank mods, but wasn't really going to pull the tank just for fun to do them.
NOW, however with the guage malfunctioning it just may be the time.
What exactly are the "Hutch" and Harpoon" mods? and will I need to replace the sending unit as well? how do I test the sending unit to see if its the culpret?
I don't want to pull the tank more than once.

 

Hutch mod is the rerouting of the lines and removal of the screens in the tank along with the addition of a filter outside the tank pre-pump to replace the screens. I used the ITP kit but there are a bunch of threads on DIY setups also. Harpoon is the cutting of the vent lines inside the tank which allows one to top up the tank much more quickly. Guzzle's page had tutorials on both.

Here is a link for the umbrella:

FORD Fuel Tank Pickup Foot Original Equipment

since I did not have a replacement umbrella on hand I used a length of hose on the end of the pipe to get to the bottom of the tank.

Sending unit should not need to be replaced unless it is bad or damaged.

 

So.....we're thinking that the plastic pick up foot somehow has failed of broken and fallen off? would the bio-diesel (B99.9) have contributed to this?
If so what is the best fix for this? certainly IF the original foot was affected by the Bio then a replacement will be as well.
I'm reading about the Hutch mod and some are saying the extra filter setup has caused pre-mature failure of the pump.....
I sure don't want to go from bad to worse....

 

The foot on my truck was completely detached and was resting on the bottom of the tank. It literally came apart into pieces as I was removing the rest from around the tube. Not sure what the material is but likely bio would accelerate degradation.

I haven't had any issues with the hose, it is double clamped to the pipe and the end is cut at an angle (Vee notch would be better probably).

The baldwin 1212 filter that comes with the ITP kit is relatively course. The inline screens people use are coarser still. The latter shouldn't be much if any more restriction than the in-tank screens were. A fine filter could cause undesirable restriction pre-pump and at least some of the discussion is related to people running unnecessarily fine filters pre-pump.

For bio you might well be better off using hose instead of a new foot or you could look into a sump like beans sells which can be installed without dropping the tank...

 

I know its a bit of a nasty job to pull the tank-I'm up for that if nessessary.
But, I don't ever want to do it again, I want to do all the mods including removing the fuel nozzle restrictor from the filler neck while I'm at it

So....Hutch, Harpoon, and the filler neck restrictor........

Whats the best Hutch setup to do? kit? DIY?

 

Kit-wise, the most complete and highest quality kit that I'm aware of is Strictly diesel's. That is the one I used.

Driven Diesel Fuel Tank / Pre-Pump Kit

Diesel innovations makes a kit also and Dieselsite has one but it is packaged with their regulated return system.

 

OK, Thanks! Supose I were to just DIY an extension on the pick up instead of re-installing anouther pick up foot, and NOT install an additional filter setup? will the factory filter in the bowl catch everything?

 

There is a screen inside the fuel pump. You really want to catch debris before it hits the pump so that screen doesn't clog up. Many use the 3007 filter which is just a mesh screen and works well.

Wix 33007 & Napa 3007 Fuel Filter: FleetFilter Secure Online Store

That is the type of filter included with the DI kit:

Diesel Innovations Complete SS Pre-Pump fuel line kit

 

honeydew, You are sure being alot of help, and I truely appreciate it!

Sounds like I should get an inline filter NOW and install so crap doesn't get into my pump screen.....I will be able to drop the tank AFTER about 400 miles or so of driving-(I just filled it up last night) So, right now I don't have any filtration due to the probable failure of the pick up foot?

is the screen in the pump serviceable or replaceable?
NOT trying to be cheap, just want to do whats best for my truck in the long haul.

The first Wix/NAPA in-line filters you show look like the cheapie ones (5/16") that we used to use on our cars (Fords) in place of the ones that fit into the carburetor......is there a difference between one like this for gas v/s diesel?

 

You're welcome! The foot does have a strainer but there are two screens still in service that have a tighter mesh than the foot so you'll be fine until you drop the tank. Those can be cleaned if you don't want to do any mods, but of course you'll have to drop the tank again if you want to clean them again in the future...

I cut up a pump, you could hypothetically bend back the tabs and pull the pump apart to get to the screen but it would be extremely difficult based on my experience. I've heard of people holding the pump with the inlet down and flushing it out with brake cleaner or diesel to try and clean off the screen.

Those filters are rated for diesel and just have a mesh screen. Don't confuse them with the similar looking ones that have a paper element.

 

Thanks Again! I think I'm going to order the Kit and a new foot from Strictly Diesel.
.....and watch my mileage until I can drop the tank and do everything.

 

Guys, I went ahead and ordered the Strictly Diesel kit, a new pick up foot, and a spare Baldwin filter for it-from what I understand I should be ok till I can run my full tank out and drop it and do the mods w/o adding (temporerely) a cheapie plastic inline filter.
I have coresponded with Dennis and he was very informative on his kit and what I can expect after installation.
Plus most everything in his kit is US made!