fwiw, I don't think that will work on Diesel- pure soap works on gasoline, but pure soap mixed in diesel fuel.... well, let's just say the soap partially dissolves into a gummy residue. I know a specific application for said concoction.

 

2X on the 7/16 NF short bolt and an O ring.

 

there is a product at boating supply places called marine tex it is a 2 part epoxy that does not react with fuel or gasoline. it is way stronger than bondo and works on about any surface. i have used it on the gas tank on my 85 bronco and it lasted years.

http://www.boatersworld.com/webapp/w...ne+tex&x=0&y=0

 

Aviation fuel tank self curing sealant. Awesome stuff. Takes a day to cure but it is forever.
Don't get it on anything other than the tank though. Once it is on, it will stay on (well, will rub off hands eventually along with some skin).
I think you can order it from Genuine, or if you have a small airfield nearby you could go and beg with the mechanics there.
-P

 

Want to know what Id do? Get a bolt, nut and a couple large fender washers and some black RTV or permatex #2. Drain the tank and put the bolt thru the hole and the washers covered in a little RTV on either side, then let the RTV cure a couple hours and crank it down.
Ive done this on aux tanks, even on the bottom, and its worked fine.
Avoid rubber products like expanding freeze plugs.. and most repair chemicals may or may not work with diesel-soaked plastic or biodiesel.

 

I would also use a bolt with a nut on the inside, preferably a locknut. I would try a nylon sealing washer on each side (like an oil drainplug washer), backed by a steel flat washer.

For a little extra insurance, I might try a little epoxy, such as JB weld, or a sealant called Seal All smeared in the hole with the bolt.

http://www.eclecticproducts.com/sealall.htm

 

I am not familiar with your truck-model; is the tank metal or plastic ??


I have had success with the two-part plumber's epoxy-putty, the stuff that comes in the clear cigar-tubes, under various trendy trade-names; just about every parts-store, Walmart, etc. carry it under one or more names.

Were I you, I would work up a dab of this putty and force it firmly in the hole, then immediately install a deep-threaded sheet-metal screw, then cover the entire screw-head and surrounding area with another glob of the putty.

It works best if you wipe the area with paint-thinner, prior to the fix; also, scuffing up the surrounding area will benefit.

I have used this stuff for years; I honestly believe it could repair a broken coupler-knuckle and hold.

 

Depending on just where the hole is, you could just ream to the correct size and install a "DrawStraw" fitting for a host of useful reasons; better/bigger fuel draw, good place to plumb in a return for a bypass regulator, good place to plumb in an auxilliary electric fuel-pump that can be used to fill tractors/etc. or simply empty the tank for whatever reason, etc., etc.

That's exactly what I would do.

 

I found out the material used in the bushings that come with the draw straw's doesnt like biodiesel. mine split and fell off a couple times so I gave up and went with nylon tube pickups, compression fittings and an barbed elbow fitting on top of the tank. Came out pretty good and has no air leaks so far.

 

I have had good luck using the rubber grommets off of tubeless farm-tractor-tire fluid-fill valve-stems; they will stand up to methanol, anti-freeze, and calcium-chloride, so I don't think anything in a fuel-tank will hurt them.