Gas Tank Question...

[Anonymous]

Okay, it finally warmed up enough for me to start messing with the gas tank I bought off Ebay. I started stripping things off, emblems, and such. The petcock was a bear BTW. Barely enough room to turn a wrench under that on one side. Anyway, when I stripped the emblems off, there's mega rust under there. One side is worse than the other, no doubt due to the fact that there was only one screw holding that emblem on, therefore allowing plenty of water under it to do it's job. On the worst side, it's very spongy under there. Is this tank still usable? Do I just strip the rust off, then seal, or what? The inside of the tank is rust free, it's just the outside that's got it. Just to be sure that wasn't a common thing, I stripped the emblem off one side of my tank, and it was fine, a little dirt around it, but must have had a good seal, as there is no rust like the other tank has.

[earlfor]

Re: Gas Tank Question...

Kay, the tank would not normally be spongy. Do you mean that if you push on the side with your thumb, it flexes a bit or do you mean it feels soft enough that if you really pushed, you could push your thumb through the side? I think you will have to get the rust cleaned away to see what the condition of the metal actually is. Once cleaned up, it will probably be obvious if the rust goes all the way through.

Earl


[quote="ladykatie"]Okay, it finally warmed up enough for me to start messing with the gas tank I bought off Ebay.

One side is worse than the other, no doubt due to the fact that there was only one screw holding that emblem on, therefore allowing plenty of water under it to do it's job. On the worst side, it's very spongy under there.

[Anonymous]

You might want to check also if the tank was previously repaired. If you have water entrapment in a bondo patch then you may get that spongy feel to it. Metal normaly doesn't get spongy without rust through of some sort.
To rectify the problem you first have to strip the tank around the patch till you see bare metal. Basically you have to find the edges of the patch so you don't miss some water logged bondo or other such filler. When you find the edge remove the bondo completely. Use a knife to remove the largest portions. Afterwards sand by hand so you don't accidently burnish a hole throught the tank. Then patch as normal with the Bondo.
Having said that if for some reason the problem is actually with the metal of the tank you have a whole other bucket of worms. Your best bet is to find a cosmetically challenged but very sound tank on E-bay. It isn't worth all the time it takes to tig weld a patch and redo the tank unless you want to do a custom or stretched tank.

Never challenge a one-legged man to an ass kicking contest, he may surprise you with a peg leg over the head.

[Anonymous]

Re: Gas Tank Question...

[quote="earlfor"]Kay, the tank would not normally be spongy. Do you mean that if you push on the side with your thumb, it flexes a bit or do you mean it feels soft enough that if you really pushed, you could push your thumb through the side?

Earl

Earl, I think that if I start scraping away at the layers of rust there under the emblem, I'd have a very nice little indentation there. By spongy I mean that it feels like you are actually pushing down on a sponge instead of a metal surface. The SO looked at the tank, and thinks it won't be too bad when it's all stripped off, but I dunno. I'm seriously considering not messing with this tank at all because of that, and the fact that when I removed my emblem on my tank, mine seems like it's in much better shape to start working with. Mine is just more dented. I guess I won't know until the darn thing is aired out and I can start seriously working on it. But I am new to all this "hands on" stuff with respect to the bike. My car, I do all my own maintenance and work on, but this bike, I am learning at. Maybe it just seems worse to me because I haven't seen a lot of other tanks stripped of their emblems. It may be a common thing I just don't know about. LOL

[Anonymous]

You might want to check also if the tank was previously repaired. If you have water entrapment in a bondo patch then you may get that spongy feel to it. Metal normaly doesn't get spongy without rust through of some sort.
Your best bet is to find a cosmetically challenged but very sound tank on E-bay. It isn't worth all the time it takes to tig weld a patch and redo the tank unless you want to do a custom or stretched tank.

Never challenge a one-legged man to an ass kicking contest, he may surprise you with a peg leg over the head.

There is no sign of bondo in this area of the tank, I think it's strictly a metal problem. This was a cosmetically challenged ebay tank, so it's not a big loss, I got a good petcock, cap and key, and emblems with it, so I'm actually ahead, even if I can't use the tank. Now I know people who weld, but they are a bit hesitant to the idea of a gas tank. It's airing out as we speak. But as I explained before, I am new at all this, so what seems like a lot of rust to me, may just be surface rust. I don't have enough experience at bike repair yet to be a good judge of how bad is "too bad". I am waiting on warmer weather before I really strip the tank and start working, as I don't have a shop or garage yet. Lil Suzi resides in a small shed during winter time, but there's not enough room or light to really work on anything in there. I stripped the emblems and petcock sitting on the front deck. LOL I don't think it goes all the way through the tank, it's only spongy to a point, then it's solid again. I may be all worried over nothing. I took pics of the tank sans emblems, and will probably throw another page up on my site sometime this weekend, so you can get a look at what I am talking about.

[Anonymous]

Just had a peek at the pics on your website. I reckon with a bit of time and effort, you will have it back to brand-new condition.
The area behind the emblems doesnt look too bad - check that the straps which the screws go into are still firmly attached to the tank and make sure that ALL rust is removed before painting or it will just bubble up again.
Have a look at the advice on painting in the 'garage section'.
Take your time, make sure that all rust is removed, fill and sand all dents and pitting and give it at least 3 coats of paint and clear coat.

I have just stripped a tank myself (it looked worse than yours), following the procedure and I am very impressed with the results. Good luck !