Plastic Weld Cracked Tank Filler Neck.

[rtbmrgl]

My 99 220 had a cracked filler neck, pretty bad, about 1/2 way around. Used and new tanks are more than i wanted to spend unless it couldn't be fixed. So I gave it a shot.
What i found the gas tanks are made of High-density polyethylene (HDPE). I bought a cheap harbor freight plastic welder, basicly and soldering iron with a flat triangle tip. I bought (HDPE) welding strips.
I got the PE plastic strips and welded the tank, seems to stick, time will tell. I covered with plastic epoxy to make it look better. I ran my finger inside the tank and felt where the weld oozed through.

I know....its ugly.

I pressurized the tank, checked for soap bubbles and the pressure held until i released, about 15min.

[SS109]

It may be ugly but, if it works, who cares! Your bike is rideable! Good job!

[KDXGarage]

If it holds, it holds! Good job.

[rtbmrgl]

Yep, time will tell. Worse case scenario, I’ll buy another tank.

[MoonStomper]

I've fixed a few plastic fuel tanks.
If that stuff peels off... do the following before giving up:
1. Clean the site
2. heat up a solder iron and penetrate the ends of the cracks to terminate their elongation
3. using your solder iron create a shallow 'trench' long the crack from end to end
4. use a razor and shave some thin shards of purple plastic either from under the tank (out of sight) or a matching plastic part
5. gently heat a shard and melt it and press it down in the crack
6. Once the crack is filled let it cool
7. sand the area starting with 200 grit up through 1200 or so until smooth and polished
8. if you followed the above steps carefully you will have effected a permanent and attractive repair

[rtbmrgl]

I've fixed a few plastic fuel tanks.
If that stuff peels off... do the following before giving up:
1. Clean the site
2. heat up a solder iron and penetrate the ends of the cracks to terminate their elongation
3. using your solder iron create a shallow 'trench' long the crack from end to end
4. use a razor and shave some thin shards of purple plastic either from under the tank (out of sight) or a matching plastic part
5. gently heat a shard and melt it and press it down in the crack
6. Once the crack is filled let it cool
7. sand the area starting with 200 grit up through 1200 or so until smooth and polished
8. if you followed the above steps carefully you will have effected a permanent and attractive repair

Thanks, great idea on shaving and using it for filler.

[MoonStomper]

I've fixed a few plastic fuel tanks.
If that stuff peels off... do the following before giving up:
1. Clean the site
2. heat up a solder iron and penetrate the ends of the cracks to terminate their elongation
3. using your solder iron create a shallow 'trench' long the crack from end to end
4. use a razor and shave some thin shards of purple plastic either from under the tank (out of sight) or a matching plastic part
5. gently heat a shard and melt it and press it down in the crack
6. Once the crack is filled let it cool
7. sand the area starting with 200 grit up through 1200 or so until smooth and polished
8. if you followed the above steps carefully you will have effected a permanent and attractive repair

Thanks, great idea on shaving and using it for filler.

I actually crashed this Saturday afternoon and broke the upper headlight fairing mounts, so I had to fix them for a big ride I had planned on Sunday. This method worked and I had no problems in spite of hitting trees and the ground Sunday. Planning on doing a write up of that job with pix.

[rtbmrgl]

I've fixed a few plastic fuel tanks.
If that stuff peels off... do the following before giving up:
1. Clean the site
2. heat up a solder iron and penetrate the ends of the cracks to terminate their elongation
3. using your solder iron create a shallow 'trench' long the crack from end to end
4. use a razor and shave some thin shards of purple plastic either from under the tank (out of sight) or a matching plastic part
5. gently heat a shard and melt it and press it down in the crack
6. Once the crack is filled let it cool
7. sand the area starting with 200 grit up through 1200 or so until smooth and polished
8. if you followed the above steps carefully you will have effected a permanent and attractive repair

Thanks, great idea on shaving and using it for filler.

I actually crashed this Saturday afternoon and broke the upper headlight fairing mounts, so I had to fix them for a big ride I had planned on Sunday. This method worked and I had no problems in spite of hitting trees and the ground Sunday. Planning on doing a write up of that job with pix.

good deal, thanks for planning the write up.

[MoonStomper]

Here ya' go...
viewtopic.php?f=77&t=24712