Sorry for putting this here, but no matter what button I push, I cannot get to NEW POST under Wanted To Buy ????
 
Chasing a NEW or as new Fueltank for my 1978 XC Coupe Hardtop, regardless of capacity
 
Many thanks for any leads  ...........  mobile 04031-64031  Bernie

Can anyone give their opinion of the best way to clean out a interior surface rusted tank. No new ones avail for XC. Only XA & XB which are missing vital EC connections. Want to keep original. I've seen these choices to date.......
1/ Vinegar with nuts and bolts chucked in and 2 guys swishing contents all around, then flush out with methylated spirit to dissolve any water, then final flush with petrol. When all appears dry, spray in a coating of WD40 ?
2/  Give local Radiator the $200 job of soaking tank in their "soak tank" with no guarantees what happens ?
3/  Buy some proprietary cleaner from an auto store and try that ?
4/  Cleaning as best as possible and then sealing inside with a supposed hermetic layer of "POR" which I'm guessing is some kind of epoxy resin ? ?
5/   ....................any other suggestions plz ?
Thanks for ANY suggestions
BV

I've done most routes. Tank cleaned by radiator shop and the old Vinegar route. No point with por 15 unless you can get in the tank and unsure if it withstands new fuel. Personally I prefer the Vinegar. It only eats rust not metal and I've done several cars and forklift tanks with it. In fact I soak lots of parts with it then clean. It is an acid but not a major acid so just clean it out with water and bi carb and all good. My Perana tank was choked with crap so I replaced with the paid for cleaned one. Then I soaked the original for 3 weeks with 50/50 vinegar water mix. You should have seen the crap that came out after then. I then poured bi carb and water in once waited swished and all was good. If a hole presents itself no idea how to fix but a weld after all that is safe to do. Vinegar is a man's rust best friend.
I'm sure the proffesionals use phosphoric acid diluted to nothing but vinegar is like 99c for 2 liters. If you have never used it on rust just satisfy yourself by soaking a rusty tool or part In pure vinegar for 24 hours and give it a clean sure you will be amazed. Oh and whack some in your toilet cistern overnight to clean it and your toilet. Hope that helps. Keith

Thanks a mil' Keith,
 
exactly as you say with vinegar is my preference too.   Nobody can give a 100% effort like yourself for your own
goal 100% of the time.  It's worth having a go yourself when you feel able and confident. Since the inside zinc lining has been eaten away due to someone who shall remain nameless added a litre of Racing Fuel (very corrosive) to a full tank of ULP , I wonder what suggestions you may have to prevent further corrosion other than adding super outboard oil 300:1 to the fuel which I do anyway as a "Valve seat saver" due to no lead in our fuel.
Maybe Methylated Spirit addition may be helpful to dissolve any future water that gets into the tank via condensation and/or water that naturally is absorbed by fuel (hygroscopic)...........i seem to recall 2% Metho is ideal ?
cheers
Bernie 

Sorry can't help protecting it after. My concern was only what it was doing to my motor (fuel filters clogged in no time). Once coating is gone it's gone. Por 15 is great but if it lifts with bad adhesion you've got more pain. 5 steps if I recall and that's when you can get to the area.

Cheers Keith

Never used it personally but heard good things about KBS which I guess has similarities with POR15 products.

https://www.kbs-coatings....-fuel-tank-sealer-kit/

KBS is better. Chassis kits as well. And Oz made

Thanks for the great input guys,
 
why I dont think any POR15 or KBS will work, is the standard XC Coupe Tank has a huge "depression" stamped into it to accomodate the spare tyre, and there's the rub. These "sealers" are less than 2 litres, and I'm guessing at the very least you should have 15-20 litres to swish around in the hope you get to that internal area where the spare is. So with less than 2 litres it's very likely to miss a portion of surface, and so the fuel will sneak under the sealer and then all hell breaks loose. Literally!
It'd be great to find a shop who can split the seam welding to separate the 2 halves and get them cleaned and re-zinced and seam welded again .............  and then I stop dreamin'!
Thanks again to everyone.
Don't hesitate to forward any suggestions.

I purchased 8% (double strength Vinegar; new line they've added) from Coles in Coles Brand and wacked in 8 litres and swished it around & brushed as best I could* every day for 5 days and it's looking pretty good inside tank.
Might add another 12 litres, plug all holes and turn it upside down to get to difficult spots like that spare tyre well.
Will report back.
* Bunnings had what looked like a Bottle Brush 1 metre long by 80mm dia and sold as "Leaf Guard" for house gutter
(Not quite long enough to reach everywhere) :-(       ....but betta dan nuffink!