Rust in a fuel tank

woodlandfarms · Jan 18, 2017

I have an 11 gallon tank on my Diesel tractor. Lately I have been finding bits of rust in my filter. Drained the tank, looked through the pour hole and yup, rust everywhere. Not sure why someone would make a tank without a coating but here I am.....

So, how to fix? The issue is access. I only have 3 holes (the out at the bottom a 1/2" for the outflow of fuel, I have two on the top of the tank, one for the sensor and one for the fill, neither more than 2" across.

Do I drain, wash and dump a bunch of Naval Jelly in the tank? Do I sand blast (no way to get the top). Do I dump a bunch of nuts in it and slosh it around? Or do I just coat it and hope the rust doesn't flake off.

Any ideas would be great. Oh, the tank is very verticle. Maybe 8" wide at the bottom and 4 at the top and 20" or so high.

RNeumann · Jan 18, 2017

I've heard good things about this-

POR-15 U.S. Standard Fuel Tank Sealer 4924 - Free Shipping on Orders Over $99 at Summit Racing

Stimw · Jan 18, 2017

A piece or pieces of chain will also work.

Egon · Jan 18, 2017

You could put some phosphoric acid plus single graded gravel in it and then do an extended shake. Flush it out good and do another acid flush and it should be good to go. Some of the cleaners dairy farmers use clean their lines has phosphoric acid in it. It may also be less expensive.

The best would be a place that can do a hot wash and then coat the inside.

prichard · Jan 18, 2017

Common on old motorcycles. The usual fix is clean out with acid followed by coating the interior with por15 or similar like rneuman linked to.

Edit: didn't see egon post. That's it.

Al 2 · Jan 18, 2017

Years ago I had a small gas tank that had a lot of rust and crud in it. I tack welded some flat bar to the mouth of a cement mixer and bolted the tank to the bar. Put in some kind of solvent and gravel from the drive way and spun it around for a few hours until it was shiny inside and then flushed it out. Like new inside.
Al

yankeerider · Jan 18, 2017

I just dealt with that problem on my '30 Chevrolet and used the POR-15 fuel tank kit. The inside of the tank was so bad it was plugging the tank outlet tube. The POR-15 kit worked very well- two washes with degreaser and one with the phosphoric acid etch before sealing it. I was very happy with the results. If I was doing a diesel tank, though, I'd be inclined to not seal the tank, instead counting on the more oily nature of the diesel to leave a film to ****** rust development so long as the tank would be kept mostly full.

TemporaryKubotaOwnerMark · Jan 18, 2017

This might be the time to look into removing that rust with electrolysis.

Once you have it clean, give it a quick bath with phosporic acid, then an epoxy coat and you're good to go.

ultrarunner · Jan 18, 2017

About 30 years ago I coated many with Fuel Tank Sloshing Compound sometimes called aviation sealer... worked like a charm...

Fast forward to ethanol and the sealer became a gooey mesh...

RNeumann · Jan 18, 2017

ultrarunner said:
About 30 years ago I coated many with Fuel Tank Sloshing Compound sometimes called aviation sealer... worked like a charm...

Fast forward to ethanol and the sealer became a gooey mesh...

New stuff says it's good with ethanol. Ethanol has been tough on older equipment and most small engines today still recommend avoiding it.

woodlandfarms · Jan 19, 2017

Well, we get at least 50 inches of rain a year, if not more. Today we were in the clouds and they were so heavy with moistures the underneath of the patio roof was soaking wet.

Yes, I could do better about not leaving the tank empty, but I cannot fill my tank all the way up due to how my tractor works (45 degree slope, if you overfill you tend to leave diesel on the ground). And the top of the tank is providing some of the worst rust.

Anyway, POR-15, will do my research. Will give the chain idea a good shaking but I do need to seal.

MossRoad · Jan 19, 2017

TemporaryKubotaOwnerMark said:
This might be the time to look into removing that rust with electrolysis.

Once you have it clean, give it a quick bath with phosporic acid, then an epoxy coat and you're good to go.

I've done a bit of work with electrolysis at home. It works great on solid stuff, however, I wonder how you'd get it to be even on the inside of a tank. You'd have to get the sacrificial anode into the tank without touching the tank itself, and it kind of has to be centered because the closest metal to the anode will get the juice, as they say. For the outside of a tank it's easily resolved by using multiple anodes around the perimeter. Still, it might be worth a try to drop a large anode down the fill hole and see how it goes. Can't hurt anything to try.

kenord · Jan 19, 2017

I have done a few tanks, and found sheet rock screws work best , because of all the sharp edges.
Also easy to get out with a magnet .
Not all tank liners work with diesel so you need to ck I am not sure about por 15 , I do know my brother has done a lot of motorcycle tanks and swears by it. but there not diesel,
have fun.
Rich

Rocky J · Jan 19, 2017

Al 2 said:
Years ago I had a small gas tank that had a lot of rust and crud in it. I tack welded some flat bar to the mouth of a cement mixer and bolted the tank to the bar. Put in some kind of solvent and gravel from the drive way and spun it around for a few hours until it was shiny inside and then flushed it out. Like new inside.
Al

We use to tarp strap them to the mower tractor wheel and go mow, some of the tanks had a lip on the inside of the fill hole and could be a pain to get the gravel out so we used nuts and bolts and used a magnet to get them back out. At that time we ordered a quart can of Tank Sealer from J C Whitney , We used a pickling vinegar as the etching wash solution. Do not know if it was the best way but at that time it was the only way to get paint to stick to galvanized metal .

yomax4 · Jan 19, 2017

other products I.ve used to coat the inside would be a product for motorcycles called Kream i think it's spelled with a K. Cycle shops can get it and also Johnson Solder makes a 2 part sealer that works well that was developed for Huge radiators on ships and trains. Radiator shops can get it and some welding supply stores that sell Johnson solder. Good luck.

TemporaryKubotaOwnerMark · Jan 19, 2017

MossRoad said:
I've done a bit of work with electrolysis at home. It works great on solid stuff, however, I wonder how you'd get it to be even on the inside of a tank. You'd have to get the sacrificial anode into the tank without touching the tank itself, and it kind of has to be centered because the closest metal to the anode will get the juice, as they say. For the outside of a tank it's easily resolved by using multiple anodes around the perimeter. Still, it might be worth a try to drop a large anode down the fill hole and see how it goes. Can't hurt anything to try.

Not a problem. Use a piece of 3/8" rebar and bend as needed. Secure it outside the tank instead of just hanging it. It might take a bit longer, but it will get the job done.

That's got to be a lot easier than shaking a bunch of metal around inside.

super55 · Jan 19, 2017

RNeumann said:
I've heard good things about this-

POR-15 U.S. Standard Fuel Tank Sealer 4924 - Free Shipping on Orders Over $99 at Summit Racing

I had use POR-15 to re-coat/seal a rusty fuel tank for an old Army Jeep. It had tons of scale inside the tank and a few minuscule pin holes in it.

Took tank off cleaned as best I could by spraying a garden hose in it to break off any scale and let the tank dry in the sun for a day. Than poured a pint of POR-15 in the tank and covered all the holes and sloshed and rolled the tank around to make sure I covered everything inside. Poured out the excess and let it dry in the sun for about 3 days.

Been almost 3 years since I did it and no rust in the tank and not leaking. Pretty easy to do but make sure you don't let the paint dry on any threads or your hands. Once the stuff dries it's impossible to remove.

stuckmotor · Jan 19, 2017

This thread reminds me of one we had recently that started when someone asked about the rust he was finding on the inside of his fuel cap. I've searched for that thread many times and haven't relocated it. Can anyone give me a clue as to how it can be found? I too, have rust on my fuel cap and would like to review the replies.

mjw357 · Jan 19, 2017

I've used these products on rusty/leaky fuel tanks with great results.

KBS Coatings - Gas Tank Sealer - Rust Prevention - Stop Rust Paint - Clear Coat Paints

prichard · Jan 19, 2017

stuckmotor said:
This thread reminds me of one we had recently that started when someone asked about the rust he was finding on the inside of his fuel cap. I've searched for that thread many times and haven't relocated it. Can anyone give me a clue as to how it can be found? I too, have rust on my fuel cap and would like to review the replies.

Use the Google search at top of page for best results. But I don't know how to make it sort by date or just thread title which would be handy.

My results: Search Results | Compact tractor forums, news, reviews, information.