MTFCA Forum

So I picked up a speedster gas tank shown in the pictures. It has a ding on the side without the seam It has some surface rust outside and in. Here is an inside picture through the fill hole There does not appear to be any rust through's or soft spots. I plan on paint less dent repair or stud welder to push out the dent, sandblasting, and painting the outside. What if anything do I do about the surface rust on the inside pictured? I have done a 1964 Honda Superhawk CB 77 motorcycle tank that leaked in the past with the load it up with bolts and shake it around exercise. Back in the day Kreem was the gas tank inside coat of choice. It has not aged well over 20 years. The Kreem has come off like a bad sunburn. Any suggestions on what if anything to do these days? Also what do you use to make tank straps out of for a Speedster? Does any one have plans for how to make speedster gas tank mounts?

Ignacio,. For making your gas tank straps you can use lumber bands. The wide steel bands that you see banding lumber loads on railroad cars. They are strong but hard to drill due to the steel used. Go to your local lumber yard to get one cut band. On my frist speedster this is what I used for the gas tank straps.

My speedster has metal cradles (one at each end ) to hold th lower section of the tank They could also be wood, and the tank is held down into the lower cradles by straps. Been good for 50 years.

Ignatio, POR 15 have a fuel tank restoration kit. There are 3 stages in the process. Just follow the steps and it will give you good service. The nut and bolt cleanout is a good start to the process.

Hope this helps,
Allan from down under.

Fired up the stud welder to get the dent out. It is better but still has creases and imperfections. Unfortunately the strap will not cover them up. That's where body filler comes in I suppose. Being obsessive I find body filler distasteful, is there a way to get the creases and imperfections out without it? I know that the issue is that the metal is probably stretched from the impact and I've heard of a shrinking disk and I've seen techniques but they seem to need access to the back side which isn't easy under the circumstances.

When removing dents, a really good method is to neutralize the fuel vapors by a simple warm water wash, followed by some dish soap and warm water about half full slashing it around every once in awhile. after a few hours rinse with cold water.

Now make up some adapters to be able to pressure the tank to 10 psi max. I use a remote portable tank for airing up tires and bleed down to 18 psi. you may want to use a pressure regulator, but 10 psi is the max with this method. Have a small propane touch ready and heat the area next to the crease at the dent.., POP goes the dent! This is the method professionals have been using for years on motorcycles. It may take a few times on the same dent, but the results will really surprise you.

Sorry I was a little late on your task, been busy!

Hank

Splashing..., I just love my auto correct!!!!!

Not sure what the girth of your tank is but here is a picture of what suppliers sell - if they wouldn't fit yours then I guess you'll have to make your own

Yes I can try this. I have ordered a 1/4" NPT thread with OD 1/2 schrader valve that I can put in the drain. Make a replacement gasket for the cap which is rotted using cork gasket material and see what happens...

Henry K. Lee wrote: ↑

Sun Jul 19, 2020 10:55 pm

When removing dents, a really good method is to neutralize the fuel vapors by a simple warm water wash, followed by some dish soap and warm water about half full slashing it around every once in awhile. after a few hours rinse with cold water.

Now make up some adapters to be able to pressure the tank to 10 psi max. I use a remote portable tank for airing up tires and bleed down to 18 psi. you may want to use a pressure regulator, but 10 psi is the max with this method. Have a small propane touch ready and heat the area next to the crease at the dent.., POP goes the dent! This is the method professionals have been using for years on motorcycles. It may take a few times on the same dent, but the results will really surprise you.

Sorry I was a little late on your task, been busy!

Hank

And I thought my OCD was bad. Doc, I ain't even gonna share ANY of my OCD thoughts!
Or can you accentuate the little foibles in the steel to show that this is from more humble beginnings?
Steel banding would be great straps for your tank like Kevin mentioned! Clean it, fold it, set it, drill it, paint it and Bob's Your Uncle.
Doc, I still don't know where that statement's from.
Looking/lurking for the outcome.
Goll dang it. That tank looks good inside.

On another note, an easy way of drying out a fuel tank is to reverse the hose ports on a Shop-Vac style vacuum cleaner making it blow instead of suck. The warm generated air drys them out beautifully in about 45 minutes.

Hank

I usually have my wife talk into the gas tank or container I'm trying to dry out ...she's so full of hot air it only takes about 10 minutes to dry

I nominate myself for screw-up of the year. Sorry to report that the 10 psi pressure method was going well. Then I took my eye off the gauge while heating and pressurized it too much (the cap leaked air a bit) blew the seam out because the solder had melted. I took it to a radiator shop which is what in hindsight I probably should have done in the first place. They put it back together so it functions as a tank again but without heroic measures it is disfigured. Not a good day.

All is good! Sorry this happened. It sounds like you were getting the hang of it until excitement struck!

Hank

I should have mentioned to submerge the end in a pan of cold water about 3/4” while working close to the soldered joints. Heat shunt!

Me bad!

Hank

Resurrected! The radiator shop metal man was good, I watched him fix it the first time but the strategy was not good. So I spoke to John T and he suggested take the end cap all the way off straighten it and put it back on. So I took it back and voila! Looks pretty good. They also metal brushed the loose rust off the inside while the end cap was off and took some minor dings out. Good enough to use I think. I didn't want to post the exploded picture because it horrified me but now that it is all back and then some check it out. Next up: he told me the sides are delicate don't sand blast. I plan on wire wheel brushing off the external rust then Metal prep then a good primer. I haven't decided on a final painter yet, maybe me. Suggestions for good primer are open. The Sherwin Wiliams Macropoxy 645 B58 W 610 primer that the blasting yard used seems like pretty stout stuff should I use that? Picture 1 Egads exploded, oof bad! Picture 2 fixed but not good. Picture 3 Pretty good.

Say any ID of what this tank is? The speedster tanks I see and are currently sold new have the fill hole in the middle while this one has it to the side.

I have no info but that tank looks great!
Can't wait to see it with primer/paint!