My 97 International 4700 needs either a new fuel tank or the original one welded up. Figuring its a steel tank and diesel, I could weld it, because it shouldn't blow up from doing so. Its the D style tank and it has a very slow seep leak under the step area. 37x25x15 A new aluminum tank is around $600, but might be able to cut the step off and weld up the holes for less. Not against getting a new one, but also found the same tank at another location for over $1000. Never bought a tang for a truck (only boats) so wonder what thoughts on this is are
I just cut the step off of probably the same tank on my IH 2375 and brazed up that same leak. Just lower the fuel level under the leak and go to it. I have welded or brazed a pile of leaks in steel diesel tanks. If they are aluminum, I let my cousin do it, because I don't have a TIG rig.
You guys do know that vaporized diesel fuel actually has MORE explosive power than gasoline? If you really have no idea what you're doing... DON'T DO IT!!! 35years ago I had a friend killed cutting the top out of an engine oil drum. Really.. Do some research because none of you will listen to me. I have repaired many tanks and I'm still here, but this "it's only diesel or hydraulic fluid" gets stupid people killed.
Kind of figured it would be easy enough. If I were even to attempt to do it, I would drain and remove the tank, then flush with water.
If I were to do it, I would flush with steam for 3 hours in several different positions, then shovel 20lbs of dry ice in there (CO2 purge) allowing for half of it to sublimate (melt). Co2 is heavier than air so keep the vents at the top, since your leak is near the bottom, seal the cap and vent roll the tank over and remove the drain fitting to allow the CO2 to purge the air out... But I really do not recommend you do this without supervision from somebody with plenty of experience doing repairs of this sort. If you have a heavy duty radiator shop nearby you may be able to get them to boil the tank clean if it will fit their hot tank... removes rust too. Actually I'm betting that your tank is beyond repair anyway if its rusted out under the straps. The pitting is going to be everywhere.
If it's already rusted that bad I'd say it's junk. You can always do the poor man's trick of draining the fuel then running a line from a vehicle exhaust to purge the air whike you weld, then have at it.
It's rusting and leaking at the step only. Bought it many years ago and started to leak in same place. Started lookin for another tank then it stopped. Here it is year later and its starting again. Don't get the difference between a 600 tank and a 1000 dollar tank other then the extra 400 dollars (different vendors). If I used the truck all the time it would be hands down new tank, but I only use it every now and then. Right now I'm using it a lot because they are doing construction and need someone to haul off the rock. I do it for free for the fill. Can always go to half tank and do it that way. Never knew diesel would blow up like gas
It's just as dangerous or even more than gasoline, when you start heating it and see white vapors... those are bad.
Maybe I should just buy another tank. Any recommendations?
If it's a tiny seep, why not use epoxy? Pressure wash the outside off, pull a light vacuum on the tank through the vent, clean the area with brake cleaner and blow off with air, and slather it with Jb weld or some other epoxy. It shouldn't suck through if it's only a seep. Welding is possible IF you know what you're doing. Eliminate the possibility of oxygen in the tank, leave the cap off but covered.
Thanks another idea I like and is worth the try
I have welded patches on diesel tanks after I have steam cleaned the inside and got it hot enough to dry itself out, then MIG weld the patch on. I’m sure to be flamed for saying this, but this is my experience. If you don’t need a step in the tank, I’ve got one that I’d give to a good home. I’m getting rid of my old stock of junk to make room for some new junk. If you’re interested, PM me.
I use fiberglass epoxy and mat for repairs like that partly because usually the talk is on its way out and getting pretty thin and rusty for welding its usually under the straps and once you start cleaning gets worse I use power wire brush,air needle scaler to get the rust off and then etch with muratic acid to get down into the rust pits clean seems to hold up for several years I'm not big on welding fuel tanks have done it with caution but prefer to avoid it
Buy the new aluminum tank. You'll thank everyone later. I ran S-series trucks for 20 years. When those tanks start leaking, they are done. You fix one leak, you get 2 more. $600 seems very reasonable for a replacement tank. You can't hardly buy a used tank for a big truck for that.
The last tank I replaced was a round one, steel, and I got lucky and found a used aluminum tank that would fit in its place. I had a drop of fuel one morning under the crane, and reached up and rubbed my finger on the bottom of the tank, and it was leaking. When I got the tank dismounted, there were several places you could push a screwdriver through it by hand. Gave $150 or so for the aluminum tank, used. I agree with Shimmy1 and everyone else when they say once it starts leaking, its done.
Decided I'm just going to replace it, so its either go see repowerguy, get a $600 (4statetruck +117 ship) or $1000 new tank. Appears the $1000 tank is made of thicker aluminum and guess 4statetrucks just make a cheaper tank. Sent an email to metal tank and see what they say
Replacing the tank toady. Wonder if I should put rubber under the tank, the steel tank didn't have any but does have it on the upper straps??? I have a 10 foot roll of 1/8 neoprene rubber. Could be if I use it it may slide out over time
I put rubber under mine when I repaired it. That was about 4 yrs ago. It has never moved.
Well I fastened it down without, but was easy enough to loosen straps and reinstall, might do it later. Its the only shinny thing on the truck now
I redid a broken tank strap a while back, I just grabbed a broken 2" yellow tie down ratchet strap, and cut a piece of strap out long enough to go under the tank strap. I'm sure its not the "approved" method, but it was what I had handy, and I figured it would give a little cushion and help to keep the tank from moving around.
If you put an aluminum on steel supports you will NEED something between them or it will galvanic corrode in short time. Any kind of strapping rubber or even used old fire hose a time or two canvas over rubber between tank, mounts and retainer straps.
Should probably put rubber under it, but the chart doesn't show that much from what I was finding. Do have the rubber and it might take 30 minutes to get it done. Do need to get my forklift starter wire fixed to make it easier