34 replies to this topic

[enderwigginau]

Molasses and a couple of electrodes.
You will be able to wash it out with water and it will eat most of the corrosion.
Final wash with metho or acetone to dry any left over water out.

Swirl a coating into it to finish it off and it will be good til you need to work on it.

Grant..

[enderwigginau]

Electrodes just like bathurst-racer says. Running a charge into the mix converts the "almost" rust and creates a layer of good metal (the layer depends on what you use for electrodes). With molasses you don't need the charge (we generally don't) but it's good and most people suggest it so I'm happy to suggest it up front now.
Soda is good, but it leaves a coating that you need to remove before doing anything else - so you can leave the thing until you want to use it but then you need to hit it with acid and then seal it.
With the molasses, you just get a clean fresh surface and you seal it then and there. Saves playing around later.

Both good, we just like molasses - it's easier for the big stuff, and most hotrod stuff is big stuff.

Grant..

[71xu1]

POR 15 do a complete tank sealing kit that comes with all of the necessary stuff to get your tank prepped and sealed.

[warrenm]

KBS Coatings make a similar product to POR15. I use the procedure that enderwigginau has mentioned, then use KBS or POR15 to seal. I have the KBS product in the tank of my LJ for just over 12 months, appears to be ok & no leaks anymore.

[warrenm]

You can get it direct from the supplier.
http://www.kbs-coatings.com.au/
http://ppcco.com.au/
Connect a piece of stainless to the positive terminal, hang it in the liquid(not touching the fuel tank)& the negative terminal to the fuel tank.

Edited by warrenm, 20 May 2011 - 08:49 AM.

[FastEHHolden]

Hot tank at local engine builder?

[enderwigginau]

Leave it for at least a couple of weeks, but as long as you can. The good metal won't eat away. Check the electrode regularly, as it will be eaten away so you may need to replace it depending upon what you use - Stainless, Zinc bar, or some good steel with no rust on it.

Check the sealer you use. The POR15 stuff we use needs to be primed reasonably soon after - it seals the surface against corrosion but is still porous. If you can make sure you use a sealer that doesn't need another coat AND is resistant to fuel, it's a one shot and you're home and hosed.

Grant..

[derrin71]

KBS has a similar product for sealing inside fuel tanks, they have a good video of how to do it on their website, just google KBS coatings.

[Statler]

Craig, i've looked into this at length because i need a new tank for my 911 also.

The 911 tank has a plastic swirlpot inside as you know. These swirlpots are made from 2 differnt types of plastic. Only 1 of which will survive the POR process. Do you want to take the gamble?

Even POR don't recommend their products for 911 tanks!

Alternatively, Pelican parts [who are the cheapest supplier of 911 parts on the planet] sell a replacement fueltank for around $500. Subject to availiability.

My advise m8.... don't bother trying to fix it! The little aircooled wonders are extremely finicky when it comes to fuel supply.

[Statler]

I'm guessing it is a mid 9 then?

Let me know if i can help m8.

[enderwigginau]

Yep, I don't think I mentioned that - if there is paint on a surface, the molasses won't attack it. So where there is bare metal and rust, it cleans it up and you can end up with a perfect painted section "appearing" on the panel. We've had this happen, and not realised there was paint there.

Good luck, and I hope the plastic survives the process.

Grant..

[fuzzypumper]

I didnt completely understand his process.
Did he do one rim in Molasses mixed with what, water? and another in just white viniger?
or did he mix molasses and viniger?