Rusty petrol tank and sealer experience

[lisbon_road]

A few years ago, I fitted a brand new petrol tank to my Ford Sierra.  I painted the outside of it patiently.  Then for various reasons, it sat in the dry garage for a few years.

 

And I tried to get it going again, to find the pump seized and the tank full of rust and debris.  It isn't rusted through and could definitely be used again (I sell everything), but I opted to replace it (again!) due to time pressures and I will be selling the car soon so wanted the best possible.  I don't know if this is caused by ethanol in the petrol attracting water somehow but the tank was almost empty, which is perhaps the worst case.  

 

I decided to seal the tank as otherwise the same would happen again.  It was clear that the new tank is clean mild steel inside with no protection, though the outside seemed nicely enough painted.  I bought a quart of Frost tank sealer, which was suggested for rather smaller tanks.

 

I sloshed it about having taped up the holes and it seemed to work ok.  The points I learned, well for sure there was too much paint/sealant.  You're supposed to drain it after and I refilled more than half the can.  So I could have managed with much less.

 

But I couldn't keep it for another day.  According the Frost, a resealed tin can explode and while that's probably just sales talk to make sure that you buy another tin another day, in those words of Clint Eastwood, 'do you feel lucky?'  No.

 

Just thought I'd share my lessons here.  

[dieselassist]

I dont know about ethanol in the petrol causing the tanks to rust; or even water in the juice; Ive been told its best 'for the tank' itself to 'store' the petrol tank with juice/petrol in it - which TBH isnt feasible if your storing same tank in a working workshop/lockup with welding etc going on...

but allegedly it stops internal rust of tank

 

...Ive pondered over this myself 'whats the best way to store them old injection' type tanks from cars ive scrapped; I end up relenting n drain the old fuel out; cant take the chance with sparks n welding going on, so the 2 or 3 that I have that I might 'eventually use' I drain n seal them - gaffer tape up the filler/sender after a slosch about with meth spirits... if they need to be revived I just deal with that when the time come...

 

...a friend of mine had a old vw beetle tank which he needed to revive (twas a spare he bought) n looked a bit internally corroded - yellowed top n bottom - long story short we welded it to the bucket/throat of a cement mixer with some small clean scrap nuts n bolts in with some meth spirits n it seemed to clean the tank out well enough for him to use...

[gigglepin]

i bought a second hand tank for one of my cars..it had been stored empty .but with the hole taped up and it was fine....funnily enough this was to replace the original tank that had gone rusty...which i had de-rusted and then treated with the frost stuff ..which then proceeded to come off in flakes inside the tank

[The_Equalizer]

I've used the Frost tank restoration stuff twice. Once on a Jag MK2 which had crap in its tank and was leaking slightly. The crap was getting itself into the fuel lines and causing all sorts of hot start problems. One particularly memorable occasion was late at night at Wythenshawe Hospital. In the end I went for a curry with a couple of good friends and, by the time I got back, it has sufficiently cooled down to get going again. Not the best place to leave a bright red classic Jag though.

 

The other was on one of the twin tanks in my current Jag XJ6 which had a very minor leak. On this occasion I just got on with the job after the experience with the previous Jag.

 

The results on both were excellent, but the job takes time to do properly. I would be happy to use it again.

[Tamworthbay]

For storing tanks long term add about 100ml of wd40 (easier if you buy it in the 5litre tubs) plus a small amount of thinners and seal up as airtight as you can. It stops the inside rusting and when you come to use the tank you can just drain it out and the small amount left in won’t do any harm when diluted with a few gallons of fuel.

 

I have tried a couple of the epoxy based tank sealers but never had much luck with them.

[somewhatfoolish]

If you want to protect tanks while you're storing them get something like Shell Ensis and slosh some around the inside, or seal up the orifices and use a desiccant.

[uk_senator]

Get it galvanised maybe?

[lisbon_road]

I think you'll find galvanising is not good with petrol especially with any ethanol or water in it.