My car sat for several months at the body shop with a little less than half a tank of 87 octane. Then I added 91 octane up to about 3/4 of a tank. Keep in mind this was CA gas with ethanol. A month or 2 after that I topped off the tank with 91 octane I got in Maine but which I presume also had ethanol.

That was in late Nov of 2015. Since Jan of 2016 the car has been with me in the Caribbean and I have yet put it back together to get her registered. So the gas has just been there. I hadn't planned on this long so I never added a stabilizing additive.

My question, is it too late to add something like sta-bil, bounce the car around to mix it, and run the engine for a good while to get the mix thru the pump all the way thru to the engine?

 

In my opinion, I would siphon some of it out, but if you don't want to do that, I would put a can of Sea foam in it instead of Sta-bil. Ethanol based gas doesn't last long and it goes bad. We have Ethanol here in Wi. I only run 87 in my DD pickup. We here, do have non ethanol 91 octane also, and i run that in everything else i have.

 

I thought we had anti-syphoning filler necks?

Good call on the Seafoam, I'll have to bring back a can from the US next month in my check bag though. Maybe I'll add in a bottle of Techron too. Maybe also an octane booster of some sort?

 

I just siphoned out my gas for a fuel pump replacement. My '87 does't have it anyway. Are you sure you can bring that on an airplane? I wouldn't think so. Maybe mail it down.

 

I'll give syphoning a try then.

Can't mail anything, it makes the cost crazy with shipping and customs duties. If I can't bring it back then I'll have to find a chemical substitute that's sold here.

 

Remove the fill cap and sniff the filler pipe. If it smells like enamel paint thinner, it's definitely bad. However, I don't know at what point gasoline goes bad; it might be way before it starts to reek of paint thinner.

It won't hurt to put some kind of stabilizer in it now and run it a bit.

 

I would try to get the fuel out rather than adding stabilizer at this point.

I was able to siphon using some flexible tubing and a hand pump on my 91. Not the quickest method but it (mostly) worked. I still had about a half gallon in there when I gave up.

For what it's worth, I believe you can disconnect the fuel pump at the point where its wiring passes through the sheet metal of the car (the front of the "hump" for the rear axle) and run the fuel pump off of 12V. I read about this when doing research on dropping my tank but cannot for the life of me find the source. Didn't do it myself because my pump was shot (hence the reason for dropping the tank). Anyway, disconnect the fuel line under the hood and run a piece of tubing down into a catch bucket, power up the pump, and let it run (adding more fuel occasionally) until everything is emptied out. Saves time and has the added benefit of letting you flush the fuel lines with fresh fuel instead of letting the engine burn off the old stuff in the lines.

 

I have seen gas with Ethanol go bad a completely ruin the fuel system. My money says the pump and filter will both need changed for it to run right again. Start with the filter and if that doesn't do it you will have to replace the pump.

 

Well it doesn't smell bad and the car starts and seems to run great.

I'll try and syphon out at least half a tank then fill with new gas and some Seafoam. At least the gas here doesn't have ethanol.

 

Instead of siphon, pump it out:
1) pull the schrader at the test port, attach a hose, hot wire the FP.
2) disconnect the supply line near the engine, route into a can, hot wire FP.

 

I thought about that but was concerned about burning up the new Walbro pump I have in there.

 

The pump runs any time the engine is running, so it can handle running for a while. Just pumping out also does not have to deal with heated return fuel, nor getting heated by the muffler, nor running after being heat soaked by the muffler.

Shut it off once it stops pumping any gas. That is, don't run it dry.

If you are really worried, pump a gallon, let it cool off / sit for 10-30 minutes. Repeat until done.

 

Ok cool, thanks!

 

Just run the engine now and then, its still ok.

 

I start her about once a month and run her for about 20 mins.

I just honestly have no idea how long fuel actually takes to go "bad" and after 8 months I was starting to get worried. Seems no one on the internet can agree when gas goes bad lol.

I might have to start travelling allot for work so I'm trying to figure out what to do if that happens as well.

 

Well, a good friend of mine that owns his own small engine snowmobile and motorcycle shop, claims as soon as 3-4 months. Ethanol attracts moisture from humidity. I know i have had to rebuild my Dads Honda riding mower's carb 3 times before i got him to quit buying that crap. Every year the mower sat over the winter, and by the next spring the gas was a gooey yellow mess. I use, by the way, a clear plastic hose so i can see the gas coming down the hose. Everybody has their own opinions on ethanol gas, but another thing to remember. When these cars were made, there was no ethanol, and alcohol, which is what ethanol is, can dry up some rubber products that are not made for it. So with 30+ year old rubbers on injectors, and fuel line seals, and fuel pumps. there is no way in hell i will burn it in anything I own, except by daily driver 2014 truck that's made for the crap. My racing snowmobiles run nonethanol race gas, my Harley and lawn mower, and ATV and chainsaw, and weed whip and generator, all run nonethanol premium. That's how bad i hate the crap and i have a ethanol plant 6 miles from my house. I really do. If it wasn't for govt. subsidies, these plants wouldn't even be in business. It cost way more to make a gallon of alcohol, than it does a gallon of gas. It get's political so my rant is over.

 

Again, I witnessed an S-10 pickup get parked for four months and the ethanol separated and settled to the bottom of the tank, completely dissolving everything made of rubber or plastic. We had to replace 'everything', pump, pump housing/float, filter and pressure regulator to get it back on the road. The only way to prevent it is to use stable in the fuel or run unleaded fuel that doesn't have ethanol in it; I run unleaded with out ethanol in all my stuff, except my cars that get driven on a regular basis.

 

I too have seen the gas just go bad quickly. I think a lot has to do with the climate its in and if it can be circulated a bit or not.

 

K, I think I'm sold on syphoning out as much gas as I can and replacing it with fresh local no ethanol gas and still adding some Seafoam.

Thanks everyone!

 

Whenever this occurs, DO NOT fill with high octane fuel. Use the lowest octane good clean fuel you can find. High octane fuel resists burning (to resist preignition). Low octane fuel is more volatile (more of the lighter, low ignition point hydrocarbons). What do you suppose evaporates out of the "old" fuel first? What do you suppose will dissolve and re-suspend settled and precipitated components in the "old" fuel?

Make sense now?