Old fuel what to do?

Well the Cat has been sitting for a while now without being started. The fuel is old but I have added additives like Sta-bil and Sea foam in the past. The fuel gauge show almost a half tank and I thought about draining it after I do some of the fixes on it and before the first start. The problem is I have no where to put that much gas. Is it safe to add fresh gas to the old and run the cat that way? Hate to try to dispose of gas the wrong way. Advice would be helpful. Also, will be replacing fuel filter before start up.

Thanks always

JR 1985 XJ6 III

How long is “a while”? Stabil advertises that it will keep it good for 24 months. To use a bit of extra caution, trundle up to the station with a gas can as many times as you have to to top it off with fresh fuel and it will dilute the older stuff.

I deal with stale gas all the time. When it’s gone really dead it’ll smell like turpentine…although this might vary according to regional blends and additives. Plus, the engine runs like hell and smokes like crazy…if you can get it started. I wouldn’t advise running the engine for very long (or very hard) if the gas is that bad.

If the engine isn’t rejecting it and isn’t smoking wildly I suppose it’s OK to just let the engine consume it…so long as it isn’t pinging/knocking. I agree with Erica about adding as much fresh gas as possible

I advertise “Stale Gas-Free” on Craiglist to get rid of the old stuff

Cheers
DD

New gas added to the old with a couple of bottles of octane booster?

My brother deals with this all the time with lawn mowers and snow blowers that people have let sit around idle. Gas over 2 years old won’t run the engine at all.
Drain out as much as you can find gas cans to put it in. Motor oil jugs, antifreeze jugs, milk jugs, 2 liter pop bottles, whatever. Save it for cleaning greasy parts. I know, no old Jag ever has greasy parts, but some Toyota or Chevy may come along saying “clean me mister”…
Maybe you can dilute what’s left in the tank 1 in 20 but its hard to guess depending on the age of the stuff. Best to just get it all out.

imo, draining the fuel tanks on an XJ should be part of maintenance,
taking all precaution against fire.

Water from condensation builds up on the bottom of tank, and rust it out

Excess fuel can usually be recycled by adding fairly small amounts to fresh fuel.
If you have a daily driver it can be used up fairly quickly that way

agree with above answer too, makes strong degreaser

JR,

I’d concur with Doug: unless the fuel smells evil, it’s worth trying to use it, and if the engine is happy with it, you should be too.

If either of both goes wrong I’d probably draw the fuel from the tanks through the filler cap as far as possible and refill with fresh fuel. Two pints of stale fuel shouldn’t hurt in 11 gallons of new fuel.

Good luck

Jochen

75 XJ6L 4.2 auto (UK spec)