classic motorcycle forum

Motorcycle Discussions => British Bikes => Topic started by: Grunt on January 27, 2019, 09:39:13 AM

Title: Fuel tank liner.
Post by: Grunt on January 27, 2019, 09:39:13 AM
Has anyone used a fuel tank liner they can personally recommend. There are quite a few about and even more horror stories, a lot of which I’m sure are the usual repeated friend of a mates neighbour stories.

I want to do a tractor diesel tank, I’ve soldered the holes, pressure tested it and swilled petrol round in it. There are no obvious leaks but would like to take a belt and braces attitude. I’ve also considered doing my Bonnie and ally featherbed tank.

Title: Re: Fuel tank liner.
Post by: JohnnyT on January 27, 2019, 10:29:14 AM
Hi Grunt.Ive used Por15 recently.Its like thick paint,you dont have to mix anything, although it does take 7 days to go off.
Title: Re: Fuel tank liner.
Post by: TGR90B on January 27, 2019, 06:52:36 PM
A bloke on another site recommends the Frost product, but I can't remember any details.
Title: Re: Fuel tank liner.
Post by: Grunt on January 28, 2019, 12:51:53 AM
Thanks for the replies. It seems that Petseal has been the main reason that chemical liners have got a bad name.

How much does anyone believe the manufacturers of the chemical liners claims that the ethanol based fuels will attack just about any fuel tank known to mankind. It doesn’t ring true to me that fuel manufacturers would be allowed to sell something that is likely to destroy a fuel tank to the extent that some would have us believe.
Title: Re: Fuel tank liner.
Post by: 33d6 on January 28, 2019, 04:21:43 AM
Fuel tanks aren't destroyed by ethanol. They rust out far more quickly is all. Ethanol is hygroscopic, water loves it. Water accumulates at the bottom of the tank to rust it out far more quickly than it used to in pre ethanol days. Of course the fact that newer tanks are made of a lighter gauge material than older tanks and therefore rust through more quickly anyway doesn't help either.  The major problem with bikes is too many people don't actually use their bikes but let them sit for long periods and then moan when they don't run properly on the odd occasion they're dragged out. Frequent use with fresh petrol continually flowing through the system is much better than letting the bike sit.

I can't see why you would line a diesel fuel tank. No ethanol content in diesel is there but you can have the standard problem of water condensate in the fuel if the thing is left idle for weeks at a time. That is why you often find on heavy equipment a decent cup sized indentation with a drain tap on the bottom of the tank so you can drain out the condensate before it gives any bother. It's just a standard maintenance thing which most owners either don't bother with or don't understand the reasons for. It's a self inflicted problem.

Just try riding your bikes before faffing about with tank liners. It's an uncommon way of preventing trouble but it seems to work.

Cheers,

 
Title: Re: Fuel tank liner.
Post by: Grunt on January 28, 2019, 07:15:14 PM
I want to do the tractor tank just in case there are some holes still waiting to be discovered. Both the bike tanks are sound, I didn’t realise it was just the fact that ethanol attracted water which caused the problems. So I shan’t do anything with them.
Title: Re: Fuel tank liner.
Post by: mike1948 on March 28, 2019, 05:30:11 AM
Two years ago I had 2 tanks, one aluminium, one steel with pinholes or a leaking seam.  Everyone I talked to had horror stories about various tank sealers, single part or two part, none seemed to do the job.  The one I found which had the best reviews and was compatible with ethanol was Caswell epoxy tank sealer.  Claimed to be ok for aluminium, steel, f/glass & plastic tanks.  I gave it a try, and it worked perfectly. No sign of separation, and hard as rock.  Check out caswellplating.com.

Mike
Title: Re: Fuel tank liner.
Post by: Grunt on March 28, 2019, 08:22:20 AM
Thanks for the reply Mike, unfortunately I can’t find it in the UK though the website does say what it’s made from, “Phenol Novolac“ so I’ll do a bit of research on that.
Title: Re: Fuel tank liner.
Post by: andytheflyer on May 11, 2019, 09:28:18 PM
Two years ago I had 2 tanks, one aluminium, one steel with pinholes or a leaking seam.  Everyone I talked to had horror stories about various tank sealers, single part or two part, none seemed to do the job.  The one I found which had the best reviews and was compatible with ethanol was Caswell epoxy tank sealer.  Claimed to be ok for aluminium, steel, f/glass & plastic tanks.  I gave it a try, and it worked perfectly. No sign of separation, and hard as rock.  Check out caswellplating.com.

Mike

I've just used the Caswell product for a 73 Tiger 750 tank, which was in good condition apart from one pinhole.  The resin seems OK and goes off hard, I had to drill it out of the petcock outlets as my bungs were not quite long enough.  I bought it direct from the Caswell website for around £50 delivered.  Not cheap, but cheaper than a new tank.

However, despite buying the recommended kit size for a 15 litre tank (mine's 12 litres) there was nowhere near enough for the Tiger tank.  The problem seems to be the big hump along the OIF frame tube as it substantially increases the surface area of the inside of the tank.  I think you'd need 2 15 litre kits for the Triumph tanks.

I did the work in a heated garage and made sure that everything was warm, even so the consistency of the mixed resin was like honey, so didn't run as easily as I'd expected.  You can thin it but I didn't want to risk ending up with a too-thin coating over the area I knew I had a leak. 

Having said that I seem to have solved my problem, even if only about 50% of the tank area has been covered.  It goes off in about 45 minutes at 70F and sets really hard.

I finished the job by applying a thin coat of epoxy to the outside of the tank where the leak had been, before filling, flatting and painting.
Title: Re: Fuel tank liner.
Post by: Rex on May 11, 2019, 09:39:52 PM
Did a BSA tank recently using POR 15. Again not cheap at about fifty quid for the three bottles of stuff, but worked a treat.