Recently I noticed that one of the fuel tanks on my truck was leaking fuel and the other day when it suddenly became a drip, drip , drip, I decided it was time to pull the tank.
Last evening after work I cleaned the outside of the tank with my pressure washer and TSP cleaner. Tonight I used the sand pick up tube attachment on the pressure washer and cleaned up the bottom of the tank.
I started out with silica but ran out fairly quick. I then switched to aluminum oxide which worked much better.
I expected to find problems under the straps or mounting brackets but what I found was lots of pits in the center area of the bottom as if this tank had been sitting in the dirt for some time. I think I found my problems...
My plan is to lead solder these holes and maybe some of the other deeper pits. Any thoughts on that? What about flamability issues? Should I wash the tank out first? Any input would be appreciated.
I've had very good results with the fiberglass fuel tank repair kits. As clean as you have it it will work very well, perhaps better than soldering and without any risk of combustion. I'm afraid any repair will be a temporary fix, the tank will likely continue to deteriorate to the point of needing replacement.
Steve has the right idea here, but he's got it after messing around with trying to fix it first. Just replace the tank. It won't get better. Replace with a aluminum one. Head for the junkyard, and get the straps for the new tank while you're at it. Also- no way would I reuse a tank after I'd been after it with a sandblaster. You won't get it all out. It will plug the filters. Hopefully it won't get past the filters. Really really hopefully.
Pissin in a strong wind! A good used tank would be best. If you have to fix that run a hose in it from a running engine exhaust pipe and cut the bottom out. A bomb requires oxygen. No oxygen no bomb or very little reaction. I accept no responsibility just sharing the idea. Then install new material. The other side probably will not be far behind. I would remove and pressure wash it out let it dry in the sun. Then there is a product for sealing tanks. One brand name I believe is called Cream. I have bought another from JC Whitney and I am sure there are others. It has to be put in the tank and the tank rotated coating all of the interior. That will be tough in a big tank like that. Follow the directions and let it dry. Have had good results. Suppose you could do your lead solder and then seal it. The sealer will catch up all your media trash as well. If those bad spots are at the straps and brackets it will require extra preparation.
Try to find a good used tank. I had a Hino with a couple pin holes under the strap on top so just used some JB weld. If the bottom is gone probably had a lot of water in it at some point and likely has rust inside. Diesel fuel tanks are much safer to weld than gas tanks but still require safe practices.
I've repaired them before with JB Bond, it worked well and the repair lasted years.
Done many with fiberglass resin and mat And many repaired at tank renu service Agreed that blasting wasnt best but you didnt get anymore though those little holes than is normally laying in the bottom of a tank
The last junkyard aluminum fuel tank I bought was $100. I don't think any fix is going to be less costly than that.
With severity of rust just replace or cut out the area and weld in a patch panel lead will not last any better than any other temp patch.
The problem is it's a gas tank and not a diesel tank so would need to be thoroughly steamed to flush out any gas that got in the pores or pin holes. Aluminum would be a good solution that won't rust out.
I almost blew my young self up when I was repairing a leak on my Volvo 265 station wagon's gas tank (hand me down car.) I thoroughly washed it out or so I thought. I was going to solder or braze the crack and when flame got close there was a huge whoosh and orange flame out the filler neck. After my near death experience and gas tank fix I found out there was a recall on the tank.
That's what I'm afraid of. I hate wasting my time.
You know, that's what I was thinking when I was blasting it... This **** is gettin' every where!
You're prolly right.
I've done several small tanks with Kreem and had good results, but they were small tanks. Like this one; https://www.onlycubcadets.net/forum/showthread.php?p=455593#post455593
Definitely not.
I was thinking about that.
It's diesel.
That musta woke you up! I was told a long time ago that if you're ever gonna take a torch to a tank you gotta 'blow it out with the torch first'.
The last used tank i bought was over $400.00. If the tank isnt just ate up a repair were its JB or fiberglass would last a few years maybe the trucks life. I have soldered with a big electric iron or old heat up with a torch iron several tanks before. I soldered the bottom of my pickup tank one time while it was on the pickup not the smartest thing but it worked.I sandblasted tanks before and never had a problem with sand. The tank was aired dryed so the sand was easy to shop vac out or presser the tank with air while sandblasting so sand dosent enter.
That would have been the most important thing to mention in your first post! Older single axle truck I think everyone figured it was for gasoline not diesel. Fuel tank is too vague and 22 posts before you mention it's for diesel? Diesel tanks are repaired everyday. Steam the tank out, cut the bottom out and have a new bottom welded on by a competent welder. Having a drain plug installed would be a good idea. I think I'd still look for a good used tank first and see what the cost was. $400 wouldn't be bad for good tank.
Thirty years ago we did patch gas tanks as well diesel. Took all external opening covers off gas tanks flushed with water then drain allowed to dry then lit remaining fumes with a torch. When burned off and out performed the patching. Was routine. Diesel was similar except fewer fumes would run a CO2 or Argon mix gas into those off welders.
Yup Old Doug, I kinda think that's more like what the price would be around here. I don't think I'd be as lucky as Crane Op to find one for a Franklin. At that price, I should just spend a little more and buy a new one like this; https://www.4statetrucks.com/fuel-t...nqCYaCyYXkcAMb7T-tSntppRFyM3TOYAaArWeEALw_wcB
Sorry Dave. Around here 'fuel oil' or 'fuel' is diesel and gas is, well.. gas. Local lingo I guess. Sorry to be so confusing.
Kinda sorta same around here, Gasoline or Naphtha as my Grandfather told me was one 'Fuel' but a solvent or just Gasoline, Diesel is a Fuel Oil.
$400 for a used one is way too much, the new one would be a much better alternative in that price bracket. The one I bought for $100 wasn't perfect, it had a dent in the one end- that would be right up against my fender- so I wouldn't see the dent. Junkyard man tried some $250 nonsense and I said $100 "its got a great big dent in it- it probably leaks- you should just give it to me". $100 the price was. Junkyard prices are and should be a variable #. Not whatever they ask for.
On those gas tanks I would really want exhaust gas running in them. The reaction from the torch could be bad otherwise. Others mentioned CO2 and argon. Works as well but costs money. Watched a man weld an aluminum diesel tank with fuel in the bottom of it while on the truck. Had it flooded with with argon.
I had a bad leak on the fuel tank on my international. I was going to just patch it until I started cleaning it up and saw how big the holes were. I scratched the patch plan and put a whole new bottom on the tank. I drained the tank, then took a circular saw with a carbide metal cutting blade and cut the entire bottom off. Bought a piece of remnant 3/16" steel from Alro and welded it on the bottom. Worst part for me was having to keep going back and finding the pin hole leaks in my welds, grinding them out and re-welding. That was 2 years ago, still looking good today and no leaks. My cost was $100 for the steel.
I put a very low amount of air pressure on the tank and use soapy water. No bubbles, no problems and never had to go back again that way.
I put about 3" of water in the tank and applied air pressure to find my leaks too. Find leaks, mark them, drain tank, grind, weld, repeat. Apparently I did a **** poor job welding as I had to repeat that process 5 times before I fixed all my leaks.
I have brazed up many holes like that in diesel tanks. A lot of times just braze a whole area.
I'm sorry, can I say that or has he been cancelled?
Braze was my first thought.
The radiator shops do a nice job on old fuel tanks ,they can hot tank them out and work safely on them . ive had some of my old lincoln welder tanks done . They coated the inside with Gylptol i believe . They have been fine for years.
That is a very good point. Problem is radiator shops are getting very scarce here. Regulations with the chemicals? Insurance? Trouble finding employees to train. It is not a job you can do on the keyboard and probably does not have A/C.
Same here, last Good close shop closed a few years back where closest now are South of St Louis and KC, BOTH a trip to get to.
The new one was $1500.00 the used one had good straps and over 10 gallons of space heater fuel that i got to keep.
Yup, and 30 years ago we had a good radiator shop around here too. Long gone now.
New tank came in today.
Just had a new cross over line made up.
Nice flag decal on the shrink wrap. Too bad it isn't on the tank !
Actually Behind the wrap, top right corner already exposed.
Looks like it's over top of the wrap, lower left is curled a bit.
Have to wait and see unwrapped!!
They should have painted it on the tank with stencils !