LCGB Forums

Just got my hands on a nice new mild steel mid-range tank. Would you seal it or just fill it with petrol?!

Hi FI
I would fill it with petrol (plus 3% oil).No need to seal it if it doesn't leak plus all the problems of ethanol in modern fuels
Grandpa

That'll do me...!

I pet seal (or equivalent) my last tank, but the stuff came off the walls of the tank and clattered around inside until I could break it up into small enough pieces to get it out. What a faff!

I am building a new tank now, but I won't be sealing it. I will weld it and test whilst dry, as described below.

Cut around the valve of an old inner tube (leave a good 2" around the valve)
secure the rubber/valve over the neck of the filler using a jubilee clip
Insert the tap, secure it and turn it off
Use a hand or foot pump to put some air in the tank
Use a paint brush to slap a strong mix of washing-up liquid and water about all the external joints (watch for big bubbles and tiny bubbles)
Re-weld any leaks and repeat until this test is successful
Fit the tank to the scooter, fill with fuel, ride like you stole it.

Knowledge wrote:I pet seal (or equivalent) my last tank, but the stuff came off the walls of the tank and clattered around inside until I could break it up into small enough pieces to get it out. What a faff!

I am building a new tank now, but I won't be sealing it. I will weld it and test whilst dry, as described below.

Cut around the valve of an old inner tube (leave a good 2" around the valve)
secure the rubber/valve over the neck of the filler using a jubilee clip
Insert the tap, secure it and turn it off
Use a hand or foot pump to put some air in the tank
Use a paint brush to slap a strong mix of washing-up liquid and water about all the external joints (watch for big bubbles and tiny bubbles)
Re-weld any leaks and repeat until this test is successful
Fit the tank to the scooter, fill with fuel, ride like you stole it.

i like your way of thinking

I find that petrol is the best thing to put into petrol tanks

I have had Petseal in a tank, but it's a pain. Especially if it breaks up and blocks the tap. You shouldn't need it in a tank that is used regularly.

If you decide to seal use POR15.

I have always used these products without issue:-

http://www.tankcareproducts.co.uk/

Rich'

Rich Oswald wrote:I have always used these products without issue:-

http://www.tankcareproducts.co.uk/

Rich'

Thanks Rich
I've been looking for something like this .

Nick, is the tank clean inside? New or used ?

Just re read your post , it's new . You'll need to swill it out and when it's c Lean fit it and fill it up , Defo no pet seal needed .
Ever !
Chemical stripping has seen to that .

I've always been under the impression that if a Lambretta,or any 2t tank for that matter,is clean inside there is no need to seal it.The reason is that a 2t tank always has a lubricant in the petrol,2t oil and that keeps the inside of the tank free from rust,as I say I've always,rightly or wrongly been under that impression and its worked ok for me.

Feersum Injun wrote:Just got my hands on a nice new mild steel mid-range tank. Would you seal it or just fill it with petrol?!

I agree that you shouldn’t need to seal the tank.

However, with old tanks that have rust, I’ve always tried to get an acid, such as phosphoric to attack the corrosion. Obviously, you need to be very careful. I’ve even used a good drain cleaner of the type you buy from Plumbers Merchants, again with lots of care.

However, this Post really reminds me of the thought I’ve long had that Lambretta tanks could be so much more flexible in size & manufacture if they were fitted with bladders or bags of the type used in Motorsport, Marine or even RC Models.

The ’tank’ then becomes just a ‘housing’ or ‘shell’ to protect the lining.

If the bladder were strong enough, you could even fit one in the toolbox that would get use on longer jaunts to increase the range whilst still allowing a few (non sharp) tools to share the space.

Sorry. I’ll get me coat...

Mel K wrote:Just re read your post , it's new . You'll need to swill it out and when it's c Lean fit it and fill it up , Defo no pet seal needed .
Ever !
Chemical stripping has seen to that .

I'd assumed I didn't need to do anything but have read threads in the past about sealing. Thought I'd throw it out there...! Someone mentioned those in tank catalyst things to me but I think they're jut nonsense...!

Warkton Tornado No.1 wrote:

Feersum Injun wrote:Just got my hands on a nice new mild steel mid-range tank. Would you seal it or just fill it with petrol?!

I agree that you shouldn’t need to seal the tank.

However, with old tanks that have rust, I’ve always tried to get an acid, such as phosphoric to attack the corrosion. Obviously, you need to be very careful. I’ve even used a good drain cleaner of the type you buy from Plumbers Merchants, again with lots of care.

However, this Post really reminds me of the thought I’ve long had that Lambretta tanks could be so much more flexible in size & manufacture if they were fitted with bladders or bags of the type used in Motorsport, Marine or even RC Models.

The ’tank’ then becomes just a ‘housing’ or ‘shell’ to protect the lining.

If the bladder were strong enough, you could even fit one in the toolbox that would get use on longer jaunts to increase the range whilst still allowing a few (non sharp) tools to share the space.

Sorry. I’ll get me coat...

Any links opens up lots of posibilities