[gary bennett]

my 63 gp. runs rough & smokes. ran good one & yrs ago. the gas has been there for about 4yrs with sta-bil iput in every year. the plugs are dry but black, choke is open, all other items are new , plugs, wires, etc. do you think the gas is that bad. it is 93 octane. thanks

[Engine-Ear]

Gary,

Note that octane evaporates over time. What was 93 octane in 2007 (and only $2 per gallon, by the way, but I digress) might have dropped 10 points! The point is, gas degrades. How many gallons are in the tank now? If less than half, I would either empty the tank and slowly burn that turpentine with your lawnmower gas or top off the tank with 100+ octane race gas.

Then I would gap and install another set of R45S plugs. Also be SURE that you have the proper voltage to the primary side of the coil (and that the coil is good-ohm it out).

Pull the dipstick - if the oil smells like fuel, drain the oil and add new oil (don't sweat the filter).

Turn key and listen for 389 cubic inches stand at attention.

Let us know how it works out.

[66bonne]

Agree with our esteemed collegue Matt. Time for fresh gas.

Jim

[indymanjoe]

Sta-bil is ok for a year..i have had bad luck with it in my dirtbikes.i honestly can't blame it on sta-bil but i swear i have more problems with the snowmobiles and dirtbikes even the rarely used rototiller that had sta-bil used..anymore i just run them empty and refill later.Specially chainsaws now that i think about it..

[pfilean]

Seems like I read somewhere a while back that gas is really formulated to last only about 60 days before it starts to deteriorate. I know that sounds like a short time and we have all had gas sit a lot longer even without Sta-bil and not really seen much problem. But 4 years?

[Deadhead]

What I have found is that I have had gas in parts cars or other situations where it has sat in the tank for a long time (years). When I first get into it it is fine, but as soon as the air hits it, it only takes a matter of hours before the whole thing goes bad and stinks like varnish.

X2 w/ Matt - Mix at least half a tank of good premium in and then run it all out and fill with fresh.

I never thought this would be an expensive part of the hobby.

[hurryinhoosier62]

Nearly ALL premium unleaded today has ethanol in it as an oxygenator. Remember, ethanol is hydroscopic. There's NO WAY that gasoline purchased 4 yrs ago is still good
today even with Sta-bil. X 3 on the recomendation.

[Engine-Ear]

Originally Posted by Deadhead

I never thought this would be an expensive part of the hobby.

For sure, man!! LOL!!!

[gary bennett]

I want to thank all you guys for your answers. I am a slow at the restoration. 7ys. ago i had the tank cleaned & sealed. now there is less than a quarter tank of gas, i will siphone out all i can, take the tops off the carbs,dry them out, unhook after the fuel pump & crank out some more & then put in new gas. I will follow up after i do all that. Right now it is off to a doctors appt.

[Stu Norman]

Sounds to me like you have a stuck float, Gary. It is probably gummed up from the stale fuel. Fresh fuel should help dissolve any crud and return your engine to smooth running.

[gary bennett]

siphoned all the gas i could out of the tank, stuffed paper towels twice down each carb & manually pumped out the gas, unhooked the line after the fuel pump & hooked a hose in to a can & cranked the rest out of the tank. i know there must still have been some left. put in 4 gals of 93 octane with some more octane booster & carb cleaner. when i got gas in the carbs it started right up. let it warm up & it ran nice & smooth. when i hit the gas a little it snaps right up.after warm up it still smokes some grey, not blue like oil.could that be from some of that old gas.i hope to get it out of the garage this week & drive it up & down the driveway (300ft) so i can turn it around in the garage to do some body work on the passenger door. i already have the front clip off & i did take the body off the frame so i could repair the frame.

[Deadhead]

Berkbile 2+2 cuts a lot of crap. Give it some good RPMs and squirt in until it almost croaks, let recover and do one more time for good measure. Let run a while afterwards. Should be back to normal.

[Engine-Ear]

Plus if you had any oil burning in the past the mufflers could need to be exercised to purge the stored oil...