Hi all,
I have an old sym husky and my mechanic opened up my carburetor and there was rust in the fuel and told me my gas tank is rusting from the inside. He said there is no way to fix it without replacing the tank, I should just use a fuel additive ever 1-2k.
Has anyone else had this problem? Or does anyone know of a fix?
Thanks
I would take it to another shop and ask them to check, if they say the same (rusting from inside) getting a new tank shouldn’t cost more than $1500. I don’t think it is easy to fix the rusting especially since it is in the tank.
Replacing the tank would be the only practical way to resolve the problem of rust build up within the tank. Rust usually builds as water residue builds within the tank. If this is a frequent problem then you may wish to drain your tank every once in a while. Also make sure that water isn’t coming in from your filler cap. Some filler caps have locks in them which can allow water ingress through the lock mechanism. You can perhaps think about changing it to a cap without a lock in this case, or seal or cover the lock.
If you can see rust in the fuel filter, or on the tap screen after removing the tap, it could come from contaminated fuel but its much more probably from the tank. If you can see rust when you look through the filler cap or any of the other holes (using flashlight, inspection mirror), then obviously its rusty.
The only other avenue of investigation I can think of is fibreoptics, which Ah Huang may not have to hand.
If you can’t confirm the rust, then “another shop” cant either, so taking it elsewhere seems a waste of time.
If it hasn’t got a hole in it, you don’t need to fix it. It may, however, be worth cleaning it.
I’d try an abrasive scouring of the inside, to disloge troublesome rust flakes before they dislodge themselves. A length of chain swooshed/clunked around is probably easiest to remove afterward, though shipyard confetti or even gravel are also sometimes recommended.
I used detergent and hot water on myy Zing tank, hosed it out and then rinsed it with ethanol followed by acetone to de water it, but that may be more trouble than you want. The acetone can get you quite intoxicated unless you’re in a well ventilated area (I was in the shower) and may not be very healthy, but it seemed hilarious at the time.
People use acids (hydochloric or phosphoric) to aid rust removal, though I didn’t, since I was mostly concerned with “gunge” rather than rust. HCL is available here as a bathroom de-scaler but I’d want to dilute that a lot. Dilute Phosphoric acid is available as CocaCola.
After cleaning, or if you buy a new tank, put a bit of ethanol in it every month or so to de-water it, and change the fuel filter.
Thanks for the suggestions
I wouldn’t mind getting a new tank but the mechanic said they don’t make them any more. The additive he said to use was an ethanol mixture that is supposed to stop the rust from spreading. He said if I do this and replace the fuel filter regularly then I should be ok.
Ducked,
that sounds like a lot of work. How long did it take you to clean it? And did it work?
[quote=“jesse.falkner”]Thanks for the suggestions
I wouldn’t mind getting a new tank but the mechanic said they don’t make them any more. The additive he said to use was an ethanol mixture that is supposed to stop the rust from spreading. He said if I do this and replace the fuel filter regularly then I should be ok.
Ducked,
that sounds like a lot of work. How long did it take you to clean it? And did it work?[/quote]
Your mechanic agrees with me, so he is a super-spanner and must be treasured. Dont let him anywhere near your motorcycle if it gets a stuck clutch though.
Can’t remember exactly how long it took but quite a lot of rinsing so maybe an hour or three, then I left it to drain/dry, with a fan blowing on it, for a day or so. May have swabbed with paper towels too, can’t remember.
Seemed to work, got some rust flakes out, and nothing much in the fuel filter subsequently. The tank wasn’t very rusty though. The carb had clogged up with “petrol porridge” from sitting a long time and I was cleaning it mostly as a precaution to remove any petrol residue. The main problem was the carb.
I didn’t know there was a specific product available for de-watering, I just bought ethanol and acetone from the chemist. Whats it called and where do you get it? MIGHT be better/cheaper.
Edit: 95% ethanol from my local chemist is 65nt for 500ml. Denatured alcohol (dyed pink, should do fine) will be cheaper but there wasn’t a price on it.
IIRC the Zing, which is a similar style to the Husky, has a little drain hole for the filler cap surround, which gets clogged. This MAY increase the chance of water ingress, though I dont know that it does.
Electrlytic treatment described in general terms here:-
http://smokeriders.com/Tech/html/electrolysis.html
There’s no specific description of the fuel tank method but the pictures tell the story. Looks like the tank is the cathode (-) and a bit of steel rod is the (sacrificial) anode (+) which makes sense.
Edit: I’d wrap some mesh (eg that green “scaffolding screen” mesh) round the anode to reduce the risk of it shorting, though I still try to avoid letting the mesh touch the tank side.
Too late if the tanks holed though. Edit: You could still use the technique if you put the tank in a plastic bag or two to contain the electrolyte, but obviously you’d have to plug the hole somehow afterwards.