LCGB Forums

I've have a twin tank conversion on my SX for many years, but today noticed loads of what was like black rubber floating round.
So stripped then out, unbeknown to me it must have had an internal coating applied after the conversion.
It's obviously now failing, the tank has baffles to make it worse.
I've put paraffin in added nuts and bolts to agitate it... Only thing agitated at the minute is me.... Its removed some of the loose, but there's still plenty left
Anyone cleaned one out successfully?
The metal underneath is in great condition

If a tank is just the usual rust and sediment type stuff, I use the cheaper option of caustic soda, followed by Spirit of Salts and finished off with Rust Remover ie Phosphoric Acid.

If it is bad and if it has evidence of some form of old sealant possibly, I can recommend the products of Tankcare Products. They have a kit that cleans the tank out and seals again in a white material. Several years after I first used one of these kits in my TS1, the sealant is still pristine. The kits do cost around £60 though from memory.

Cheers Paul, it's definatly a coating, like a black rubber.
Frost do "tank strip" which sounds like it should do the job.
The tank surface looks decent.
I'll have a look at tankcare.

Might just buy a a big tank... Not sure I can be arsed farting about.

2 things you could try:-
1. Blast it clean using a proprietry pressure washer. With luck this will get to the difficult to reach bits.
2. Put a couple of handfulls of old nuts, bolts or screws into the tank and put the cap back on, then wrap the tank in some foam or a piece of old duvet and secure using bungee cords and then put it into an old pillow case and knot the end. Then wait until the wife has gone out so you can put it into the tumble dryer on a low heat setting for 40 minutes or so. Remove, tip out the crap, inspect, repeat if necessary. No elbow grease required.

New day...
I like the look of the twin tank so will persevere
Tankcare do a product that you put in and seal the tank, the vapours then strip/debond the coating and you then flush out. Will ring them tomorrow to discuss.

Can't order any potions today so gonna have another go.
I've got a fair bit off already.

Both tanks were flushed clean last night with water and dried with compressed air. Stuck an endoscope in and I have removed a lot, the area each side of the baffles is the worse.

I've not got a jet wash, but used my hose on the move powerfully setting.

Fortunately Mrs Gaz is away this afternoon so it's the nuts and pillow case method....

Read last night to try a paint stripper.

This could well be a couple of silly questions.....

What would happen if the lining flaking away was to effectively be captured as it occurred by a capable, serviceable filter? Is the debris too large that the existing taps (with in-tank filters removed) would clog? It seems to me that unless every trace of lining can be removed, there will always be that nagging doubt.

The other (silly) question is as to whether freezing the tanks might somehow be instrumental in breaking down the lining remnants?

It's coming off in the tank in small pieces but bigger than sand/grit, but in the toolbox bigger pieces. Toolbox is nearly cleaned, hopefully the tumble dryer might sort that.
Some pieces were as big as 20x10mm from the toolbox, was able to fish and shake out.
The tap filter was clogged up.
Its noticeable better after some work yesterday.
Gonna buy the Tankcare Petseal remover product tomorrow for the tank (then do a rust treatment)
The added problem is the tank is baffled.

Most tank sealant failures can usually be traced back to poor preparation rather than a poor product.
I use POR15 petseal and never had a problem.
A cup of Cellulose paint thinners works well to get rid any any traces of oil in the tank. (Unfortunately, we can't use tetrachloride anymore)
If there is any internal rust then this has to be arrested first with rust stop else the petseal won't stick.
I double coat the tank to make sure it gets to everywhere.
I pour all the stuff into the tank and tumble it for 5 mins, then pour out the excess back into a container and seal tight.. Let the tank semi air dry for a day and then pour what's left back into the tank and tumble for another 5 mins before draining out the excess.
It's best to let them dry out for at least a week before filling with petrol. (even longer in the winter) The curing time bit is important. The longer the better.

the best tank cleaning I've seen or done myself was....
soda blasting, get in touch with onsmallwheels (s Wales) saw a tank rusty as you like came back as new.
the other I did myself on my tank after trying petseal which failed miserably and had to be cleaned out first using petseal remover.
OXALIC ACID 1:3 ratio with water and left over night or 48hrs depending on severity of rust.
flush the tank with cold water and use bicarbonate of soda to neutralize the acid(mine was finewithout bicarb)
the dry the tank rapidly with hair dryer or heat gun to prevent flash rusting
add your petrol/oil which will prevent any rust build up.
hope this helps
saw the method on line but ca't remember who did it.
certainly did my tank fine.

lam1962brettagg wrote:the best tank cleaning I've seen or done myself was....
soda blasting, get in touch with onsmallwheels (s Wales) saw a tank rusty as you like came back as new.
the other I did myself on my tank after trying petseal which failed miserably and had to be cleaned out first using petseal remover.
OXALIC ACID 1:3 ratio with water and left over night or 48hrs depending on severity of rust.
flush the tank with cold water and use bicarbonate of soda to neutralize the acid(mine was finewithout bicarb)
the dry the tank rapidly with hair dryer or heat gun to prevent flash rusting
add your petrol/oil which will prevent any rust build up.
hope this helps
saw the method on line but ca't remember who did it.
certainly did my tank fine.

I've never felt compelled to line a Lambretta tank with anything & hearing of the issues that can arise, I doubt I would want to. The latest fuel additives seem likely to make any issues worse IMHO.

In the 80's when I had old VW air cooled vehicles, a KG Typ III had a really rusty tank that would block the inline fuel filter in less than 50 miles. The only way to keep mobile (other than taking the tank out & doing a proper job ) was with a shot of Redex in every tank fill.

Fortunately, we add our own particular type of oil every tank fill in any case, which as lam1962brettagg says, should keep the formation of rust @ bay.

However, having mentioned modern fuels which may contain ethanol, the hygroscopic factor being the main concern in this instance, it's an issue as to how a complete Lambretta should be stored for a period of time unused

It seems to me that we are going to have to dispose of unused fuel that is six months old maximum & pour dewatering fluid into tanks of machines stood idle for any length of time.......

Daft suggestion

Wizzer the top off - get it blasted and weld the top back on.

Guessing it depends on whether you know a painter & a good welder

bookertmgs1 wrote:Daft suggestion

Wizzer the top off - get it blasted and weld the top back on.

Guessing it depends on whether you know a painter & a good welder

depends how much work you want to create and how much of a mess of the 'original' tank mate

Tank and toolbox are powder coated so don't want to rip them apart.
To blast them internally would need them opening up.
Waiting on a call from tankcare about the Petseal remover and rust treatment.
Input appreciated.

dont need to open them up Gaz. they can be soda blasted as they are.
re my last post.

Why not get it acid dipped?

missing lynx wrote:Why not get it acid dipped?

using OXALIC ACID as mentioned in previous post above does not harm paintwork it will remove rust.
infact any rusty bits can be treated in a solution of this in a bowl.

Rust is not the problem, its the unknown coating to remove first.

getting in the tank and toolbox is a problem - the tank has baffles and the toolbox has a only a 19mm hole and a 12mm hole (to connect pipes to)

Spoke to Tankcare today and he advised as its not an epoxy coating (petseal etc) to use Acetone to dissolve the coating.

Weekend job !

Plus I can finally get these false nails off

Weekend job !

Plus I can finally get these false nails off[/quote]

lam1962brettagg wrote:

missing lynx wrote:Why not get it acid dipped?

using OXALIC ACID as mentioned in previous post above does not harm paintwork it will remove rust.
infact any rusty bits can be treated in a solution of this in a bowl.

I was talking about taking it too a paint stripper and getting him to dip it in the acid tank

Well some success, the old false nails are off # and the 1st tank is on blocks with the Acetone in....

# Not getting any new ones until these tanks are back in the bike...