When I got the first batch of “welding” sticks they worked well and were easy to use taking into account that I am a ham fisted Luddite. As I practiced I got better. However, as I used them all up quite soon, I bought some more and they have been nowhere near as easy to use and the results have even somewhat worse than the first batch. They were from different suppliers so I would say if you get some be prepared to hunt around for a good source and don’t use the first of a new batch on an important job.

The first batch I used to fill holes up to 5mm diameter successfully, the second batch I had to melt the metal I was meant to be welding together before the stick melted so no use whatsoever.

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You will have to do without pocket handkerchiefs, and a great many other things, before we reach our journey's end, Bilbo Baggins. You were born to the rolling hills and little rivers of the Shire, but home is now behind you. The world is ahead.

Is there an identifiable difference - a different supplier or name or something, or do they vary at random? There seems to be an almost infinite number of suppliers with only the word before 'weld' changing - Lumiweld, Alumiweld, Technoweld, Easyweld (or was that EZweld?) Durafix, HTS-2000 etc. They all seem to be claiming the same thing but it would seem they're not all actually the same product. How do you choose one over another?

Sounds strange to me. With all types of epoxies and polyesters that are available. Some thin sheet to cover the hole from inside.With super glue. To support epoxi / polyester from outside ??

If you can repair fuel tanks, water pumps... why not carburetor ?

I think the first ones I got were Durafix - I am by no means sure though. I can’t even member if I git them through a Facebook ad or eBay. Visually they were a dull silver grey rather than the shiny silver that subsequent suppliers sent.

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You will have to do without pocket handkerchiefs, and a great many other things, before we reach our journey's end, Bilbo Baggins. You were born to the rolling hills and little rivers of the Shire, but home is now behind you. The world is ahead.

I only know the epoxies that are available to the general public, and probably not all of them. Some years ago I went into a car spares warehouse in Utah to buy some epoxy for emergency repairs on my glasses and they must have had 50 different sorts available. None of them were sold as suitable for spectacle repair (not surprising really!) and they wanted me to sign a waiver saying I'd bought the stuff I selected against their advice.

Whether any of them were sold as suitable for fuel system repairs I don't know but the easily available ones in the UK don't work. Over the last year I've tried blocking up the hole, patching over the hole, etc with a number of different materials - including polyester - and eventually they all leak and patches fall off. My latest attempt before recently finding a replacement float bowl was a stainless countersunk 1.6mm screw pushed through from the inside and sealed in place with JB Weld (+ a nut on the outside). That had survived a few days on my 'leak rig' but just about all the attempts last a few days.

Maybe petrol isn't what it used to be - well, I know it isn't as it's now 10% ethanol, but whether that makes a difference I don't know. And neither does anyone else I've asked including some well respected engineers on other forums. Or maybe epoxies, like paint stripper, have been so h&s sanitised that they no longer do what they used to.

Lateral thinking - finding a way round a problem - is a useful mindset to be able to call on if you end up in trouble on a long trip, and I'm probably as good at it as anyone. Any of my previous attempts to block the hole would have been good enough as a 'shade tree' repair and would have got me out of trouble if it had happened on a trip, but longer term you need something more permanent. If there is a petrol proof (as opposed to 'resistant') epoxy (unlikely with the mindset above) I'll be sure to get some but I've not found any yet. Fortunately I now have an intact replacement and the carb now works without leaking, but I'd still like to repair the original.

True. There are plenty of "chemical metal" repairs. And epoxies such as JB weld etc.

I've seen a lot of repairs done this way. Some have lasted. Some have not. They are BRILLIANT for emergency repairs. Especially on radiators, crank cases etc. The trick with those (like most things) is preparation. Clean materials. Contaminants removed (grinded down) and cleaned up nicely. And when you've got to that stage it seems daft to use an epoxy when you could have a permanent brazed or welded repair done. Assuming you're in the position to do so.

I wouldn't use an epoxy or metal putty on a float bowl. You're fighting against the highly potent solvents in the fuel and also against gravity. And the risk of peeing fuel out of your carb when it fails is not a small one. I also wouldn't want any kind of epoxy or putty failing inside my carb either. When they fail, they crumble and break up. And that just screams 'BLOCKED JETS' to me.

@backofbeyond.

If you're in the UK, you're welcome to send me your float bowl and I'll see what I can do with it on a wet winters Sunday afternoon. I have a high-tech AC TIG welding set up and also a decent brass brazing set up along with all sorts of sanders, grinders etc to clean up small parts. No guarantees of success but perhaps worth a try.

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Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.