BSA Owners' Club Workshop Discussions

The BSA Workshop => Singles => Topic started by: Drew on 24 Oct, 2021, 18:06

Title: Petrol tank resin/liner issue
Post by: Drew on 24 Oct, 2021, 18:06
Hi all, well this is my first post as I try to get my late father's B31 back on the road. Removed the petrol tank to drain it, shaking it I could tell it was full of loose bits. Emptied the contents and it was full of loads of bits of what I assume was the resin that was put in years ago when my dad first restored it. So, is this usual? What could have caused it? What should I do to replace it?
thanks in advance!
ian
Title: Re: Petrol tank resin/liner issue
Post by: chaz on 24 Oct, 2021, 21:01
probably as its old, it had old fuel in so not an ethanol issue for today.
in that case maybe not cleaned well enough first time and petrol opened it up and moisture got in and peeled.
as it probably hardened might have had a knock and cracked.

needs blasting inside where possible and nuts and bolts treatment then derust etc before re coating.
Title: Re: Petrol tank resin/liner issue
Post by: cdsdorset on 24 Oct, 2021, 21:35
Tankcare do an excellent remover for old liner. Just pour it in and leave it till it evaporates then shake out the flakes.
Title: Re: Petrol tank resin/liner issue
Post by: Crazy Mike on 24 Oct, 2021, 21:43
I suppose it all depends what you hope to achieve here ! There is much written about the cleaning, de-rusting and sealing of tanks on this forum which I found very helpful when going through the same process with my B40 earlier this year.

It's likely your tank will need a good clean to see what lies underneath the disintegrated liner. Hopefully not too much rust but if there is, then there's a bit of work ahead !  However, once re-sealed and completed, it will give you some reassurance going forward.

I did see in the 'For Sale' section back in September, some Frost tank stripper for sale !
;D
Title: Re: Petrol tank resin/liner issue
Post by: Greenfield on 25 Oct, 2021, 08:23
I've also used tankcare three times on different tanks and had no problems. They sell the full kit for derusting and lining. Take your time and follow the instructions to the letter and everything will work well. I've used stone chippings to help clean out any loose rust.
Title: Re: Petrol tank resin/liner issue
Post by: cdsdorset on 25 Oct, 2021, 08:59
This is anyone you know with a cement mixer becomes your new best friend.
Title: Re: Petrol tank resin/liner issue
Post by: Mike Farmer on 25 Oct, 2021, 10:24
 :) :) :)

Hi
I get out as much as possible by just shaking, Then I use a length of chain on a piece of cord instead of stones or nuts and bolts cos its eaier to get out. Shake like the devil the tip the bits out---shouldn.t be any big bits now.

Then Put it under water and derust it with a battery charger.

Mike 8) 8) 8) 8)
Title: Re: Petrol tank resin/liner issue
Post by: Drew on 25 Oct, 2021, 17:50
Thanks for all the advice. The fact that Tank Care actually sell a product for this exact purpose is at least comforting in that I'm far from the only one to suffer this! I'll get their sealing kit and have a go.
I like you electrolysis effort Mike, any more details on what exactly is required to de-rust like that?

Cheers,
Ian
Title: Re: Petrol tank resin/liner issue
Post by: chaz on 25 Oct, 2021, 18:19
Ian
the reason a product exists is mainly due to the  previous tank liners were not  necessarily ethanol proof and with ethanol being introduced in greater percentage it tends to loosen and ends up blocking the fuel supply.
Mike has previously done a thread on how to derust using a charger
Title: Re: Petrol tank resin/liner issue
Post by: Martin S on 26 Oct, 2021, 14:46
Quote from: Mike Farmer on 25 Oct, 2021, 10:24
:) :) :)

Hi
I get out as much as possible by just shaking, Then I use a length of chain on a piece of cord instead of stones or nuts and bolts cos its eaier to get out. Shake like the devil the tip the bits out---shouldn.t be any big bits now.

Then Put it under water and derust it with a battery charger.

Mike 8) 8) 8) 8)

I'm intrigued, can you explain more about this? What do you do and how does it work?
Thanks
Martin
Title: Re: Petrol tank resin/liner issue
Post by: Mike Farmer on 26 Oct, 2021, 16:58
 :) :) :) :)

Essentially its the reverse of electroplating plating.

You require. A plastic bath/tank large enuf for your item
A battery charger I suggest 12V cos thats what I use.
Some common kitchen washing soda---Tesco etc
A piece of iron/steel as a "sacrificial receiver" An empty bean tin etc is fine.

Fill the bath with warm water to cover item you will see from my pic that I did it in two halves.
Put in a slack handful of soda and dissolve it (mix it well in)
Put in your rusty bit and place your receiver as close as possible without touching.
Connect battery charger--polarity is important. So +ve to the "bean tin" and -ve to your rusty bit. Ensure you have seriously good connxtions. You may have to file some gunge away to achieve this
Switch on charger. I put mine up on high charge.
Watch carefully and within a couple of minutes you should see bubbles tracking toward the "bean tin". Eventually your bean tin will go rusty.
You may have to do this a couple of times and you may well have to change bean tin. My best ever result was using an old clean brake disc.

Its cheap and cheerful and it works for me

Mike 8) 8) 8)
Title: Re: Petrol tank resin/liner issue
Post by: Mike Farmer on 08 Mar, 2022, 22:25
 :) :) :) :) :)

I've just dragged this up from the archive to save opening a new post.

Mike 8) 8) 8) 8)
Title: Re: Petrol tank resin/liner issue
Post by: Beesy on 09 Mar, 2022, 11:31
I'll second the electrolysis method. Excellent results with minimal effort.

I just did the tank internally. Filled it with the soda solution. One battery charger terminal on the tank, the other on a sacricial anode dangled inside the tank.

Did it for two cycles of 3 days each. Came out like new.
Title: Re: Petrol tank resin/liner issue
Post by: Dean Southall on 09 Mar, 2022, 13:03
If you just wnat to de rust the inside of the petrol tank you don't need to soak tthe whole thing in a bath. Simply bung the petrol tap holes, fill the tank with the water/carb solution attach the +ve to the tank and suspend stiff bit of wire in the solution in the tank, making sure ita cannot touch the tank or it will short out and attach the -ve connection.
I might have the  + and - the worng way round but you can easily look up the correct way (I can't be bothered ;-)
Title: Re: Petrol tank resin/liner issue
Post by: Mike Farmer on 10 Mar, 2022, 12:03
 :) :) :)
hi

The reason I do mine in a tank is that it draws the gunge out as you can see from the above pic. A lot of the stuff that is loosened is not metallic but garbage being held by the rust. If you do it in a tank it will largely float free.

Mike 8) 8) 8)