Phosphoric acid vs electrolysis

[nurse]

Hi all.  Need to tap the collective knowledge!!

I'm about to re fit my fully serviced carbs (thank you randy) and was gonna make sure the tank was all rinsed out when i noticed a little bit of rust on the roof of the gas tank.

Now I have read up and am half way between choosing to use a phosphoric acid clean out or an electrolysis (to which I am leaning more towards tbh - seems far more conservative). Anyone got any experience of either.

After that though I need to prevent flash rusting. Have heard about shaking oil about in the tank or using epoxy based liners.  In relation to the epoxy treatment (as well as putting anything in the tank other than fuel) What are the potential risks to the fuel level assembly and sender unit?  The epoxy looks really thick/viscous, won't it gum up the fuel float assembly??

Thanks in advance for your thoughts.

[Harvy]

Which ever method you use to clean the tank out, I would be removing the petcock and sender unit first and sealing the holes with masking tape or whatever first.


Harvy

[FJ_Hooligan]

I used expanding rubber plugs (available as a freeze plug replacement at your local auto parts store) to seal the gas cap and fuel level holes.  The petcock I taped over and clogged the screw holes with tape so the coating wouldn't contaminate the threads

[twangin4u]

Coating the inside of the tank  with anything just sounds like a bad idea to me.

[FJmonkey]

Coating the inside of the tank  with anything just sounds like a bad idea to me.

If done properly it is a good long time fix. But I have seen the problems when not done properly...

[Bones]

I put a tank liner in my little Suzuki about 7 yrs ago, still seems to be holding up well, but then again we have a choice still with what fuel we use, and I don't use anything with ethanol in it as I have heard it can affect it.

Maybe now they have brands that are ethanol compatible.   

[Steve_in_Florida]

Rust in the fuel tank is bad. The metal is so thin that any corrosion is likely to be the point of a pin-hole leak. Once you start seeing the bubbles under the paint, it's just a matter of time.

Tank liner products CAN prolong the life of the tank, but once that rust-cancer starts, the tank is due for replacement.

If you decide to "invest" in a tank liner, then you want to remove as much of the rust inside the tank as possible. Electrolysis is slow, but effective. Phosphoric acid is more of a finishing treatment on a mostly-derusted tank. Muriatic acid works a whole lot quicker, and is VERY aggressive. (works a treat for cleaning sacrificial anodes)

You MUST neutralize the acid with water and a mild alkali. Then you must remove all the water prior to using the liner product. (denatured alcohol, acetone)

I used Kreem on a tank many years ago, with good results. I followed the directions supplied with the kit.

Naturally, you will remove both the petcock and the fuel level sending unit. Electrolysis, acid, or tank liner will fuck `em up!

All told, you might want to look for a better tank. They are available, at least today...

Steve

[Mark Olson]

If you do use a tank liner ....follow all directions , do not skip steps . It will turn out badly .

[fjfool]

If you do use a tank liner ....follow all directions , do not skip steps . It will turn out badly .

+100 on this statement