How do you fix cracked gas tanks?

how big is the crack? can u snap a pic?

I don't think there's anything that works...

JB weld won't adhere to plastic very well, unless you can find some plastic specific product at a hardware store or something.

I have heard plastic welding is pretty easy, maybe google that.

Maybe look into the stuff to repair RV and marine tanks. It needs to be in the same plastic family, so to speak.

If you use jb weld, use a soldering iron to weld the plastic back together and then just use the jb weld for filler afterwards. You can eliminate the leak just through the welding and then the jb weld will help reinforce it from recracking

Clean it out with Dove dishwashing detergent and take it to your local body shop (or find a bodyman who rides) and have it plastic welded.

Planetminis classifieds. You can probably find a good condition tank for 30-50 shipped.

You'll never stop a gas leak in a cracked tank. Get a new one.

Plastic weld. Back in the late 80's I had a buddy who cracked his CR250 tank at the filler neck. He tried every type of sealer made to no avail. One day I was sick of hearing about his nads burning and took after it with a solder gun and a piece cut from an old rear fender. I heated the cut piece in a glass container until it liquefied, then using the soldering iron I would melt the tank and pour a little bit of the liquid into the melted crack. It was a messy sonuvabitch but after sanding it down, then polishing, it was barely noticeable and held up great.

You guys would be amazed at how good plastic welding can be done. Thats what i'd do. If it turns out ugly, sand the weld a bit and throw some graphics on it. You should be under the $50 limit.

i have a ttr 125 with a cracked tank...

ive tried everything including plastic welding...nothing works unless Im not prepping it right

people want over 150$ for a ttr tank...

I have a 1983 Honda CR250 that had a 1 1/2 long crack in it when I bought it. I watched a few videos on plastic welding and since I went to welding school and was pretty good at soldering from years of RC cars, I decided to give it a try.

The first time I did it, I just melted the top layer and it looked real good, but it only held up for a short while. Then I remembered the first rule in welding school was, Penetration !! I could feel the crack just inside the filler cap and there was no Penetration, So the second time I did it, I really pushed the soldering iron in really deep into the plastic so when I was done, I could feel the raised melted plastic from the inside. It has now been over a year and it is still holding.

I demo'd a new nitrogen plastic welder the other day. That's some sweet stuff for the low, low price of nearly 4 grand..... I just don't do that much plastic welding.

Option 3 gave me a good laugh!

Reminded me of one of my neighbours kids that got his first car and modded the crap outta that thing. He took a good little car and ruined it as he was in no way shape or form mechanically minded. I got pestered every time he screwed something up. I didn't mind at the start, but it became an almost daily thing with often little or no thanks. One day he asked me to help him remove all the wheel nuts (he had installed these stupid purple anodised aluminium things that rounded off when you tried to take them off). Out came the 9" grinder and I did a real nice number on them....part out of necessity and part out of badness!

He never came back after that......

A red hot flat head screw driver!

Hmm...does fuel and an ignition source go together?

Plastic welding has come a long way and is a very good option. If you can find somebody with the equipment, you might be able to get it done for less than $50. Also, the better the equipment, the better the weld. Somebody mentioned a nitrogen plastic welder earlier. That seems to be the top-of-the-line right now. There are hot air welders, and airless welders too. Air is better than airless, especially when it comes to how the repair looks. I have been using an airless welder for a few years and have had very good luck with it. I have repaired a cracked plastic MC fuel tank that held up just fine. I have also repaired a cracked plastic radiator on a Pontiac and it didn't leak a drop. The bummer with the airless welder is that the repairs are not that nice to look at, even after filing, sanding and polishing. It is apparent that a repair was made.

Here is a link to the welder I use: http://www.urethanesupply.com/Airless-Welders-1/Model-6-Airless-Plastic… They have many other options as well.

Bret

Now you have me laughing. As long as the tank is full, all is good! Welding shop teacher in high school would lay under an old Suburban with a 40 gallon full gas tank and stick weld a leak. My ass was watching from across the parking lot.

as long as it isn't diesel that has been compressed at a 20:1 ratio.


PLASTIC WELDING! like many have said. ...and not by you, by someone who knows wtf they're doing.

Call MGM Plastics In San Marcos, CA and see how much they charge. They welded some plastics for me years ago
and it held up fine.
TM