Gunk in gas tank
 

I'm trying to get a 29 Model A started.

The flow out of the gas tank is minimal. I've removed the shut off valve.

I know the car was parked for a number of years in a hot location, and I suspect gas evaporated leaving something that looks like shellac in the tank.

As far as i know, the tank was never sealed.

The goop around the the threads isn't hard.

Help

Please

Re: Gunk in gas tank
 

well Ive had several old As that havent run for awhile and full of crap in the tank


I take a garden hose and fill the tank and let it run for say 45 minutes, the majority of the rubbish comes out. then I take a shop vac and duct tape it to the filler and BLOW
air through the tank with the shutoff valve removed. It is usually dry within an hour. DONT SUCK the air- BLOW.
Then pencil filter, replace valve etc and good to go. If there is still fine rust, then check pencil filter every so often and clean or replace till tank is clean. I also run MMO.


this is the lazy mans method and has worked every time for me.

Re: Gunk in gas tank
 

Gordon,
I have cleaned tanks in the car using carburetor cleaner and also phosphoric acid referred to as "metal prep" or generic, and much cheaper,"Driveway cleaner". It is a bit costly because you need to fill the tank about half full and let sit for some time.

The last one I cleaned was much cheaper and worked pretty good. A half tank of E85. Yes,, available at the pump at least in California and somewhat cheaper than gasoline.
I left in a couple of days and shook the car whenever I walked by.

RICHARD
Anaheim CA

Re: Gunk in gas tank
 

Acetone! shake around leave set for a while! Strain and redo till clean as can be.

Re: Gunk in gas tank
 

Ethanol is a great solvent to get rid of varnish residue from gasoline. Over time E10 will dissolve it but the sticky residue will stop up your fuel filter and carburetor.

Re: Gunk in gas tank
 

Richard,

I assume that the E85 gas dissolved the residue from the old gas that was left in the tank; however, that wouldn’t take care of any rust in the tank. I suppose you could also use 5 gallons of something like Rust911 for the rust.

David Serrano

Re: Gunk in gas tank
 

Get the gunk out - water and/or mineral spirits should do just fine. I used Evaporust in my tank to clear the rust. I bought a 5 gallon bucket of Evaporust. Soaked for a couple of days, then turned the tank upside down and soaked for a couple more days. Now I run ethanol free fuel and have no problems with the fuel tank. Evaporust also does wonders for the cooling system.

Re: Gunk in gas tank
 

Richard,

I assume that the E85 gas dissolved the residue from the old gas that was left in the tank; however, that wouldn’t take care of any rust in the tank. I suppose you could also use 5 gallons of something like Rust911 for the rust.

David Serrano

Yes, that would be more effective but I was looking for a quick cheap way to dissolve the gunk from old CA gas. Some of the rust would be released with the gunk and I rinsed the tank with water and air dried.

Re: Gunk in gas tank
 

My tank was so full of rusty particles when I would poke a stick in the tank it sounded like crushed potato chips. I pulled the tank and flushed it thoroughly with water hose. Flushed out enough rust to cover my drive. Used Rust 911 mixed four gallons and let it sit 24 hours, rotating often. Let it dry. Used Ospho to coat the inside for another 8 hours. Flushed it thoroughly to remove the rest of the residue. Drained and let it dry two days. Re-installed the tank and all seems to be OK.

Re: Gunk in gas tank
 

I am a fan of Acetone as a solvent for your gasoline residue gook. Rebuild the gas gauge with a kit available from parts suppliers. Add a screen into the inlet port of the gas shutoff valve. The screen is also available from suppliers.

Re: Gunk in gas tank
 

Hi Dalton. ...
A question:
Did you have any problems with the old finish on the outside of the tank? My tank has 1964 nitrocellulose lacquer that is in reasonably good shape and would like to not disturb if possible
Thanks
Fearless