Drywall screw through gas tank

kuips

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I recently acquired a 1986 Phazer. I plan on running this on vintage rides and also letting my 2 young kids ride it in a few years. The oldest turned 2 in June. ;)!

Anyway, I noticed the kid I bought this from used a drywall screw to connect 2 panels together and ran the 1.5" sucker right through the tank. If the screw is kept tight, fuel does not leak. But I fear once I bounce down a trail that hasn't seem a groomer in a few days, it will loosen and at that time will have a big problem on my hands. Not to mention all over my bibs.

Is there a product available that won't be affected by the fuel when it comes in contact? I was thinking to use silicone sealant. Looking for some recommendations.............. Thanks.
 

there are a few tank sealers out there. most are merely bandaids or snake oil and wont last. i have mixed results with plastic and petroleum. plastic tank is a different ballgame vs steel. first and foremost look for any that are impervious to oil and fuel and give it a shot. shop for the ones compatable with the plastic tanks on the newer vehicles.

i have a tank if needed. in your case, just for the safety issue with the kids, i would just about give it up for shipping costs plus a bit for my time.
 
Yamaha tanks are polypropylene. Nothing sticks to it so don't waste your time on sealants/glues.

Weld the hole shut with a soldering iron. On a small screw hole like that I would use a somewhat pointed tip. Get the iron hot. Push in on the hole a bit. Warm and move the plastic out then back into the hole. Lay the tip of the iron on it's side and level the patch.

Fixed many this way. Different tips work better for different issues but it is the way to go. If you try to glue/seal it and it doesn't hold (it won't) you will make the job of welding it harder because of the stuff you put on/in it.

Good Luck,

opsled
 
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Stab a 3/16 aluminum pop rivet in there and put some silicone in the hole on that. I poked a couple holes in the tank on my moped with drywall screws and this was my solution. Hasn't leaked yet in 3 months.
 
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opsled said:
Yamaha tanks are polypropolene. Nothing sticks to it so don't waste your time on sealants/glues.

Weld the hole shut with a soldering iron. On a small screw hole like that I would use a somewhat pointed tip. Get the iron hot. Push in on the hole a bit. Warm and move the plastic out then back into the hole. Lay the tip of the iron on it's side and level the patch.

Fixed many this way. Different tips work better for different issues but it is the way to go. If you try to glue/seal it and it doesn't hold (it won't) you will make the job of welding it harder because of the stuff you put on/in it.

Good Luck,

opsled
x3 plastic weld for sure. If you cant do it find a shop around you that deals with plastics and have them do it.
 
http://www.askmehelpdesk.com/chemistry/mending-tear-polypropylene-547395.html

You cannot repair a damaged polypropylene gas tank with epoxy or a plastic tank repair kit, because gasoline will quickly dissolve the epoxy and the leak will reappear. Polypropylene is a thermoplastic, which means that you can use heat to melt the plastic and create a permanent repair in the polypropylene gas tank. To heat the polypropylene, you need to use a specialized tool that has a controlled heat output. This reduces the chance that you will scorch the surface of the gas tank, which will result in an ineffective repair.

Instructions:

1. Drain the gasoline from the polypropylene gas tank and remove the damaged polypropylene gas tank from the vehicle, per the vehicle's repair manual, with the mechanic's tool set.

2. Remove any gasoline residue from the gas tank by pouring 1 pt. Of acetone into the damaged gas tank, swirling the acetone around in the gas tank and pouring the acetone into the 1-gallon plastic bucket.

3. Pour a small amount of acetone on a clean rag and wipe the damaged area of the polypropylene gas tank to remove gas residue from the outside surface of the gas tank.

4. Allow the gas tank to dry thoroughly before proceeding.

5. Plug in the plastic welder, turn the heat control knob to 575 degrees Fahrenheit and set the plastic welder aside to preheat.

6. Set the polypropylene gas tank with the damaged area facing up.

7. Place the speed tip against the damaged gas tank. When the surface of the damaged area starts to melt, drag the speed tip across the damaged area to tack-weld the surface of the polypropylene.

8. Align the speed tip with the start of the tack weld, slide a length of polypropylene filler rod into the speed tip, and push the filler rod into the melting tack weld.

9. Drag the plastic welder along the tack weld while pushing the polypropylene filler rod toward the surface of the gas tank.

10. Clip the polypropylene filler rod with the side cutters when you reach the end of the tack weld. Slide the speed tip over the cut filler rod to fuse it to the surface of the gas tank.

11. Lay multiple passes of filler rod if the damaged area of the polypropylene gas is wider than one width of filler rod.

12. Allow the welded area to cool thoroughly before you reinstall the gas tank in the vehicle.
 
I use my 30 year old pistol type soldering iron. It came with a tip that is about the same shape and size of a dime. For filler (if needed) I use the shavings from a donor tank that I get from cutting into it with a circular saw.

First tank I did was a 76 SRX tank that was cracked by the rear mount (a bad spot for them). A 2" long crack around the radius just ahead of the mounting bolt.

I used a donor (SS440) tank to practice. I sliced a 3" cut right through the tank with a utility knife. I then used the dime shaped tip on end to plow down into (not through) the crack to open it up and expose the depth of the plastic. This created a furrow where the slice was. I then layed the tp over at an angle and plowed the material back into the furrow. Layed it the other way to plow the other side and then turned it flat to smooth things out.

It was easy and I got it perfect on the second try. I fixed the SRX tank using the same method with the same results. This was a weak spot on these tanks so after the crack was fixed I layered plastic over the entire radius to build it up and strengthen the area. When I was done you couldn't tell where I had been working. It was easy.

This may not work on all plastics but does with poloypropylene.

And I will restate, No glue or JB weld type stuff will work on polypropylene..............................

opsled
 
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thanks for all the feedback.....

looks like I will be getting the soldering iron out. I do not have a "donor" tank to practice on, or to get shavings from, but I do have an old gas can. I think I will run a screw through it and practice on that before making the actual repair! I will shave some material from it and use it to make a puddle, kinda like when welding metal.
 
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