How to clean a fuel tank out?

[tight fart]

I've got an old car I'm trying to bring back to life, its stood for 10 years plus.
About 2 months back I started it for the first time, I'd drained the tank put about
10 litres of fresh fuel in and got it going, started easy and all sounded fine (ish)
Today I tried to start it again, put about 3 litres of fresh fuel in but it wouldn't start,
I ended up draining the tank again an the fuel had gone off completely.
Now I thing the fuel tank needs cleaning before trying again
Any tips on cleaning out an old steel tank in situ?

[227bhp]

Your assumptions of what is happening are probably wrong, but cleaning out what from the tank?

[tight fart]

This is the fuel I took out of the tank today,

[normalbloke]

Phosphoric acid.

[Evoluzione]

tight fart said:

This is the fuel I took out of the tank today,

Yes, but what is it?

[tight fart]

Evoluzione said:

Yes, but what is it?

That was a mixture of 8 week old petrol and fresh, the fuel that came out when I first drained it stunk the garage out and was nearly black. I'm guessing there's a residue left in the tank that's contaminating the new fuel.

[Evoluzione]

tight fart said:

Evoluzione said:

Yes, but what is it?

That was a mixture of 8 week old petrol and fresh, the fuel that came out when I first drained it stunk the garage out and was nearly black. I'm guessing there's a residue left in the tank that's contaminating the new fuel.

Then you need to find out what it is and deal with it that way, only you can do that bit, we can't see into your tank from here. If it's corrosion then that is the path to follow, not wherever you've been going up till now.
Fuel doesn't go into that state in weeks or months on its own, you can start a post 1990 (ish) fuel injected engine after years of being stood and it run ok. Fuel goes a bit dark golden and smells a bit off with age, that's about all.

I'm assuming that is bad camera work and that you haven't had a wk in there too, or is that creamy addition something else?

[tight fart]

That's just the sky reflecting

[tapkaJohnD]

Is that all the fuel from the tank, or just a sample?
Either way, use that fuel to run your lawnmower - I got eight gallons out of a car I rebuilt!

After draining, flush with more fresh fuel. If you can remove the tank, give it a good shake with half a litre of new fuel in, drain, repeat three times.
Then leave some fuel in there a few days, drain and inspect.
Has it changed colour or consistency? Any bits floating? If not, try starting the car again.
If there is something going on in the tank, then deal with it.
Rust, previous attempts and de-rusting or using "sealant" can break down and give you 'bits'.
The "sealant" could be deteriorating with modern leadless, alcohol-containing fuel.

Either way, thorough cleaning is required, and steam cleaning best. I don't mean wallpaper steaming, I mean live steam at 100C, that will take the flesh off your bones.
Big truck and other commercial repairers/service centres may use them to clean their vehicles' undersides - ask around.
Otherwise boil it out, off the car, over a heat source WHILE FULL OF WATER. The last will prevent pockets of vapour that could ignite.
A powerful detergent will help - ?a couple of dishwater tablets?

Good luck
John

[tight fart]

Thanks John, that was all that came out, and I put it in the Land Rover to thin down the chip oil as winters coming.
I'll have to look at what's involved to get the tank out.

[Petrolhead_Rich]

remove tank, pour in suitable amount of cleaning agent e.g. white spirit/petrol etc, swish around, drain, repeat.

HTH

[powerstroke]

Thinners seams to be good at removing the varnish and gummy old fuel , think you will need to remove the tank and slosh the stuff about , leave to soak slosh and drain .....

[PaulKemp]

I used Frost tank cleaner I think it's from the POR range
Very efficient

[anonymous-user]

Bilt Hamber Surfex HD did a good job cleaning out the gunk from a kart fuel tank left standing for 5 years or so.

Very impressed as it dissolved the thick gunge as well.

[tight fart]

After buying a cheap inspection camera, that dosen't take very good pictures
I managed to get this image of the bottom of the tank? (inside)

Edited by tight fart on Sunday 20th November 10:24

[E-bmw]

Seeing that pic there is only one way I would put that back in the car........ In the boot to take it to the scrappy!

New tank.