Cleaning out Fuel Tanks

[Johnjackbogart]

Hey all,

Having some issues with my 91. It's started to randomly stall out, sometimes at stoplights. It can run, but still having issues with the fuel system.

I'm going to replace the fuel sending units and the mechanical fuel pump, hoping to do the fuel lines as well.

But I was wondering if I should clean out the fuel tanks, if so, how? Also, any tips for draining the current tanks or what will happen once i actually replace the sending unit (do I need to crank the engine over a ton to get air out of system?)

Anyone have experience to share here?

Thank you!

 

[Johnjackbogart]

Also, any tips for actually dropping the tanks if there is fuel in it?

 

[IDIBOBS]

Transmission jack or 2 guys on there backs usually works for us.

They make a special tank cleaner but make sure you get one for plastic tanks. I’ve never actually needed to clean a tank in my 35 years of working on cars. Might be the shower head on the pick up broke off? Are your lines leaking? Tank selector leaking? What’s your fuel pressure at idle? Have you changed your fuel filter recently? Any fuel leaks at the injectors or pump?

 

[franklin2]

The tanks for these trucks, if you have the standard pickup bed, are not expensive. Just get new ones, especially if there is rust outside and inside.

You can try one of these from Harbor Freight to get most of the fuel out. The tank is pretty heavy with a lot of fuel in it. If you can get this jiggler pump going, it will drain the tank fast. So have some containers ready.

Self-Priming Copper Jiggler Pump

Amazing deals on this Self-Priming Copper Jiggler Pump at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

You must be registered for see images attach

 

[DougBoy66]

I cleaned mine by dropping it out and carefully tossing it in the scrap pile (it had a hole in it) and installing a new one with new guts. I will point out this post (mine)is of no help. Other than it is working excellently

 

[Kdo58]

Save yourself a headache, get a large tank for the rear. And get rid of the front tank.

 

[Old Goat]

You can remove the Bed with a Cherry Picker, move the truck forward. ( I don`t know in Ohio with all the Salt/Rust)
Pull the senders and look into the tanks to see what may be in there if anything.
The Senders are in a depressed area of the tanks, and there is a Lock Ring that holds the Senders tight. Maybe with the Salt it is so rusted never get it apart?
Soak it with Kroil for a day or so and knock the lock Ring back and forth with a Brass Drift to loosen it.

When I pulled my bed after 30+ years on the 86, both thanks were clean except for some broken pieces of the Shower Heads.
Fished them out and replaced the front Sender and Shower Heads ..As mentioned above, I changed the rear tank to a 38 Gallon one.
A Spectra F26E. You will need to lengthen the suction tube and lengthen the Float Arm, and tweak it to calibrate it, if you want to go that rout.

I did need to move the Spare Tire to the bed, but did find a factory option bed mount. No way was I going to drop a Spare Wheel which weighs more than I do, under the bed with my skinny lil a r s e.
I use the front tank as a transfer to the rear tank.

As mentioned, if you stay stock and the tank is rusty, just replace it.
You could temporaryly install an electric pump to pump up the Fuel to purge out the air w/o needing to crank over the engine so much.


Just throwing stuff out there.


Goat

 

[quickster]

It's not the sending units or lift pump.If yer tank is all muddied up you will burn thru fuel filters to the point where you could buy a new tank. Believe me i know just get rid of the old tanks. Trust me

 

[onetonjohn]

Just went through this. The shower heads were all broken up in the tank. I speculated that a chunk got sucked up into the pipe and gave me trouble. New senders, shower heads, floats. Pulled the bed to get at them. Replaced bed bolts with superduty ones, so it will be easier to do this in the future. Not too bad. Let us know which way you end up going.

 

[miked]

What onetonjohn just did.
I did it exactly the same.

I also sprayed fluid film on the top of the tanks after they were installed and before putting the bed back on.

The top of my old tanks were a corroded mess from the road salt

 

[Jesus Freak]

When I got my tow truck there was about an inch of not an inch and a half of a really stiff jello type substance on the bottom similar to the jello they served in public schools except it was grey.(Though I think they gave us grey jello from time to time at Milton High School to make us more gently conform to socialist standards.....)

Anyway, i dropped the tanks and that stuff came out in chunks. The secondary tank on the right side of the tow truck is plastic, so it was okay and I pressure washed it out. When I cleaned the metal Ford tank on the left it revealed a bunch of pin holes that the jello had been graciously clogging and I got another tank.

And REMEMBER: don't eat yellow snow or grey jello...... it's for posterity.....

 

[RSchanz]

Floor jack and loosen the bolts which I would highly recommend soaking in penetrating oil well ahead of time. Oddly mine we're clean but I have cleaned motorcycle tanks with vinegar and bb's and you just shake it around every day and let it sit for a week. After I did this I coated the inside but most of this nonsense is because I wanted to keep the painted tanks. You can find videos on youtube.

 

[kbenz]

once I seen the price of a new one I just junked the old one