Re-setting spinning tank nuts. Best glue?

[Danwarb]

Hi Guys,

I'm renovating a spare tank.

I've removed the spinning tank nuts simply by using a hand held drill, an Allen key bit full speed clock wise, then using a crow bar to prize up and out each nut. The plastic melts easily because of the friction on the spinning nut. I removed each nut in about 1 minute each.

Now I'm going to widen each hole carefully with a scalpel. I don't want to grind down the nuts as I want to have maximum purchase from the exterior of each nut to the adhesive I use to reset them back in place.

In reading the 'how to' section on this site about this I've seen you guys have used JB weld.

Has it worked well?

If not what glue, adhesive or epoxy has worked for you?

Cheers,

Dan

[London_Phil]

BE WARNED

There is very little meat behind the inserts.
Go hard, and you will have a petrol leak.
Oh look, my fav subject....

[Danwarb]

BE WARNED

There is very little meat behind the inserts.
Go hard, and you will have a petrol leak.
Oh look, my fav subject....

Hi Phil,

Thanks for this. Got it loud and clear !

I've found the best way to widen the holes is to simply use the original nut, screwed back on to the bolt, then an allen head bit in a hand held drill and 'spin' the old nut back in to place by melting the nylon the tank is made of. It's worked really well on the first hole but now I need to gouge out some built up nylon right in the bottom of the hole so I'm using a drill bit by hand and carefully twisting it. It's slow !

What adhesive or glue have you found to have worked to re-set the nuts?

[London_Phil]

I used a scrap tank to play with.

I was lucky, I got all my screws out without too much pain.

Then did this using 6 x 30 allen set screws. Then its like a tappet, I can tighten against the allen, not rotate into tank.
Once the inserts are set, you could do the same?

[Danwarb]

I used a scrap tank to play with.

I was lucky, I got all my screws out without too much pain.

Then did this using 6 x 30 allen set screws. Then its like a tappet, I can tighten against the allen, not rotate into tank.
Once the inserts are set, you could do the same?

Hi Phil,

this is really interesting but I can't fathom what you mean sorry? 

Why use 6 x 30 allen set screws when there are only 10 holes on a tank?

What do you mean it's like a 'tappet' to tighten 'against the allen and not rotate in the tank?'

[London_Phil]

Ok, sorry, need to be clearer.

So you need  the following.

10 x 6mm dia x either 25mm or 30mm long Stainless set screws
10 x 6mm serrated flanged Stainless nuts
10 x 6mm id  x 18mm od Stainless washers
10 x your original washers.

Assemble one set screw into each insert , using plenty copper grease.
Then add rubber and stainless washers.
When you tighten the nut, you then use an allen key to hold the set screw still, and rotate the nut on it, and then you are not applying rotational force to the insert, and it wont spin.
You can then be confident your never have issue with spinning nuts again, unless you want to!!

Hope that makes more sense.

Regards

Phil

[Danwarb]

Ok, sorry, need to be clearer.

So you need  the following.

10 x 6mm dia x either 25mm or 30mm long Stainless set screws
10 x 6mm serrated flanged Stainless nuts
10 x 6mm id  x 18mm od Stainless washers
10 x your original washers.

Assemble one set screw into each insert , using plenty copper grease.


Then add rubber and stainless washers.
When you tighten the nut, you then use an allen key to hold the set screw still, and rotate the nut on it, and then you are not applying rotational force to the insert, and it wont spin.
You can then be confident your never have issue with spinning nuts again, unless you want to!!

Hope that makes more sense.

Regards

Phil

Ah ! GOT IT ! Brilliant Idea Phil. After all though I'd rather use the original dome head bolts.

What glue do you recommend to re-set the original nuts in to the tank?

Cheers,

Dan

[Mustang]

I've had excellent results with jb weld
others have had disaster.
go figure

[Danwarb]

I've had excellent results with jb weld
others have had disaster.
go figure

Hi Mustang,

Thats interesting . . .

Did you buy your JB weld in the UK?

Might it be a good idea if I was roughen the outer edges of holes I'm to set the tank nuts in to?

[ssevy]

 A body shop may be able to weld those back in place with nylon welding rod. It's a special technique, but is holding up well on my fuel tank petcock area.
Also, JB Weld makes two different epoxies for plastic. Call them to get the correct one if you go that route.

[Danwarb]

A body shop may be able to weld those back in place with nylon welding rod. It's a special technique, but is holding up well on my fuel tank petcock area.
Also, JB Weld makes two different epoxies for plastic. Call them to get the correct one if you go that route.

Thanks Ssevy !

This explains why Jaydub says that JB has worked well for him and not for others.

I'll go with your advice to find the best suited JB weld but what I'll also do is roughen the sides of each hole to ensure as best adhesion possible. I'm tempted to bite the bullet and get the tank either touched up re-sprayed by a specialist.

[JayDub]

Thanks Ssevy !

This explains why Jaydub says that JB has worked well for him and not for others.

I'll go with your advice to dine the best suited JB weld but what I'll also do is roughen the sides of each hole to ensure as best adhesion possible. I'm tempted to bit the bullet and get the tank either touched up by a specialist or re-sprayed.

I used the Marine version, coz it said it's fuel resistant, don't be tempted to roughen the inside of the hole as the nylon is very thin in there... I used the original nuts and didn't alter them in any way.
I left a lip around the hole so that the repair was held in place once hardened - just like Mustang did.  Follow the 'how to' and you won't go wrong.

[Madruss]

Yes the "Marine version" of JB Weld is the petrol resistant type.
I've used it on my tank. All good so far