old gas... big concern?
 

Ok, when my car blew up in August 2005, i drained the tank of the contaminated diesl/gas mix. i wiped down the entire inside of the tank and changed the fuel filter. I put in about 3 gallons of good fresh gas in at that time. The car ran for <2 min, before the motor hydrolocked and blew up. The car then sat till march '06 untouched. i finally got the engine out, and the fuel lines were left open.

... fast forward to the present...

I am getting close to firing up the new engine, but im thinking about that gas in the tank. it was about 3 gallons back then but due to evaporation i figure there is around 2 maybe left in it. maybe it doesnt evaporate that much but maybe with the fuel lines open? anyways, i got a siphon setup today and did my best, i pulled 1.5-2 gallons out of the tank when the siphon stopped pulling anything out. so at most i have a gallon or so still left in the tank. It was BP 93 octane. How bad is that to leave whats left? Of course I'm going to get at least 5 gallons of fresh gas and pour it in before i try to start it. hopefully thatll dilute it enough.. I just really dont feel like dropping the exhaust and pulling the tank all over again over 1 gallon....

advice?

if there is only a gallon at most left you can certainly dillute it enough to besafe. throw in a can of dry gas just to take care of any condensation that has built up over time.
i would try to fill the tank with fresh gas right off the bat though. the more good gas teh lower the chances of any issues.

:stupid: i would load it up with fuel system cleaner to...just in case there still diesel in the lines

theres no diesel anywhere in the lines. all lines were blown out, fuel filter and regulator were replaced. Injectors were also replaced with new ones. So diesel is not a concern anymore.

5-10 gallons of fresh gas and a bottle of dry gas should do it.

yea that'll do

awsome paul! can't wait to see you get your baby runnnin'

guess i missed out on your orginal post......did someone put diesel in your LS1??

kinda... i got gas at a Shell station(i think thats what is was, so long ago) and it was really 2/3 diesel and 1/3 gas mix... i made it home, did a header install, then the car wouldnt run right after a few min. after messing with stuff, draining gas tank etc, a week later #1 rod hydrolocked on startup due to a wide open injector. byebye motor. i already had nj department of weights and measures at the station 3 days after i got the gas and they couldnt prove anything but they did say tanks were cleaned and refilled in the past 2 days...so i was out of luck. my warranty covered a new engine, but i did extra mods so its been in the works for the past 1.5 years...

I would put in dry gas and fuel system cleaner then FILL it all the way up. That way if there is anything left in your tank it will be diluted to the point where it shouldn't matter.

You should always mix fuel sabilizer in your gas when you dont plan on using the car for a while.

well it wasnt much of a choice not to use the car, with redoing the complete drivetrain i figured dropping the tank again wouldnt be a big deal. plus i had no timeframe to fix, could have been days or years.

i have a possible stupid question... does the gas develop a lower octane level when is sits? if thats the case would octane boost do the fix? or does it just flat out go bad however that means?

the actual octane of the fuel takes many years to decay, what happens more is that anything in the tank and any impurities in the fuel will settle to the bottom around the pick up. also, over time, while the fuel evaporates out the vent air that gets drawn in condenses and you end up with water in your gas.