Nasty gas tank

[gerhed]

Ok kids, I'm looking for some advice. My old 83 has bad gas in it. I syphoned out as much as I could. I had put about 10 gallons in on what I thought was a dry tank, but I guess there was a gallon of so of bad in there. Well, the new gas went bad in about two weeks, and boys, I mean bad. So, short of dropping the tank, and possibly replacing it, what can I do here? Can I just put fresh gas in and drive it out a couple times and stop this, or is a new tank about my only option?

 

[PrairieDrifter]

Ok kids, I'm looking for some advice. My old 83 has bad gas in it. I syphoned out as much as I could. I had put about 10 gallons in on what I thought was a dry tank, but I guess there was a gallon of so of bad in there. Well, the new gas went bad in about two weeks, and boys, I mean bad. So, short of dropping the tank, and possibly replacing it, what can I do here? Can I just put fresh gas in and drive it out a couple times and stop this, or is a new tank about my only option?

Depends what it looks like coming out. Pull as much of the old gas out then put some fresh in and go drive the rest out.

Would maybe do it a couple times. Just to make sure it's all out.

If it looks rusty, you'll be miles ahead just getting a new tank and sending unit.

 

[gerhed]

It ain't rusty, just very yellow and smells of lacquer. Was causing a stutter, maybe. Old quadrajet had issues. Anywho, yeah fresh gas, new carb, drive the **** out of it. Fingers crossed, lol.

 

[gerhed]

Whew, whole shop smells like somebody been finishing furniture down here. No wonder it was missing, lol

 

[TotalyHucked]

Throw some B12 Chemtool or other fuel system cleaner in for the next 2-3 tanks too, that'll help clean all that varnish out of there

 

[PrairieDrifter]

Maybe some marvel mystery oil too. Don't stick any valves!

 

[Grit dog]

Seafoam is supposed to dissolve varnish as well.
Guess the question is can you dissolve it and the gas still be good enough to run it? Not something I have the answer to.
Best way imo would be to drop the tank and clean it out, which I understand trying to avoid if everything works fine with the sender and it’s not rusted out or leaking.
Sort of a gamble to keep throwing $ at gas if you have to siphon it back out.
I’ve not dealt with a car with a varnished tank but an old snomachine (more prone to running poor, detonating etc than a 4s engine imo). Don’t think the gas ever dissolved the varnish over several tanks. Because I kept picking up flakes of it in the fuel filter for an entire winter.

 

[90Supurban]

Might want to travel with a couple of extra inline fuel filters for a while if you're breaking that varnish free. Reminds me of a Roadkill episode where they recovered some vehicle that had a known nasty fuel system. They stuck about 4 inline fuel filters in the system in series, yanking the first one in line each time the car started to get starved of fuel.