Gas Tank Repair

[frankster]

Hi Guys,

What is the best way to repair a hole in the bottom of an old mini bike gas tank. I don't have pictures yet, I'll post them soon. The tank is off an old speedway Superstar and I think its going to be hard to find. My brother is a good welder, but I'm wondering what is the best method. Tig, Mig, brazing, etc? The hole is small and is located at the boottom of the tank. Unfortunately, the hole is close to one of the 3 mounting bolts on the bottom.
Again, sorry not pictures yet.

Also, what is the best method to clean the rust out of the tank?

Thanks
Frank

 

[tommie d]

Frank,
I can't answer your first question about welding as I am not a welder. As for question #2
There are lots of options out there for cleaning rusty tanks, like the liners from POR and other companys, and they work great. But I like to keep my bikes Vintage and choose not to use them. That's just my own personal opinion.
Here is my recipe for cleaning a rusty tank. One quart thin oil, two cups of old nuts & bolts. then shake, then shake some more. rinse and repeat. After awhile the only thing left is some dark spots where the rust once was. I leave it at that and use a fuel filter. At the end of the season I pull the tank and swish a little more oil around in it. When I'm ready to ride again I just rinse the oil out then fill it back up with gas and go ride.

 

[Fat Boy]

tank repair

Hi I have had good luck fixing the holes and cracks and leaking bracket welds by soldering the holes shut with a good radiator repair solder , make sure you clean the area good and use a good rosin to clean and treat the area before soldering . The solder is a soft lead that sands down good and I have no trouble filling and painting it afterwards . I always wash the tank out with water several times and put my air hose in the tank for several minutes to air dry then set it in the sun for a few hours and smell inside to decide if its ready to solder or rinse out again .To clean my tanks , I use the acid wash the local Redi-Mix company washes their truck drums with as it will remove rust fast from the unpainted areas , If Anyone Uses This Process Please Wear Googles Or Safety Glasses , I soak it for a few minutes to few hours it depends how bad the rust is as I have had to repeat this several times depending on how thick the rust is . When you get it to your liking rinse out very very well with lots of clean water to neutralize the acid and oil with WD-40 because the clean metal will rust fast without a protectant . the soap wash hasn't hurt the paint but it might make that spot shine more if spilled on . I have done both repairs to several tanks with good results . It may not be proper but that is how this ole boy does it . Have Fun On Your Run
Fat Boy

 

[supernova]

If the hole is due to rust you must first determine the extent of the damage. Then decide what your best option is, tank liners work great but rust never sleeps and it is a temporary but possibly long lasting repair! A good used replacement is your best bet and if you gotta use the liner while searching for one then do so, a radiator repair shop might be able to assist you or possibly fix it permanantly depending on the damage. Also a good metal fab guy could reproduce it for a price, possibly a very high price! Good luck!

 

[smallbikes88]

the speedway superstar is a real rare bike. I heard there was less than 10 built. This is a pic of one restored. It has the same gas tank as the tt 500 or any of the 68 69 rupps, and i have seen them on some ruttmans. Its a very expencive tank to find so really try to save it! I wouls try brazing or something else thats low heat so you dont burn through the tank, also coat the inside with kreem.