Old Fuel/ Petrol

[SMOKE GREY]

My car has been standing un run since late March while the engine and box has been done, taken far longer than anticipated for various reasons. There is about 3.5 gallons of Shell optimax in the tanks, my question is, is it going to create problems? Do I need to drain it off? Or mix with new fuel. Any thoughts, or advice welcome!

[iain1967s]

I face the same situation every year, when I bring my mini out of winter hibernation (East Coast USA, so it sleeps from Halloween to Easter). Except that here we have 10% ethanol in the fuel, which makes it go off even quicker...

All I ever do is make sure it's laid up with less than half a tank, and then brim it with new fuel so it mixes in with the old. Generally it'll run rough on the old fuel, and needs choking all the way to keep the mixture rich, but it's good enough to drive the mile or so to the nearest gas station that sells premium grade.

My F56 MINI on the other hand, just wants to throw check-engine lights from 'too lean' oxygen readings as soon as it's been standing with old fuel for a couple of months. I haven't driven that since March, but the classic mini has been out several times this summer

[Polarsilver]

my pet subject be in Minis or Audi URq .. if it were my car that age of Petrol would be drained off & used as weed killer (as i do not know how otherwise to dispose of old e petrol ).
i then use Briggs & Stratton "Fuel Fit" added into the Fresh Petrol this stuff is designed for overwintering Mowers & Chain Saws to keep this crap e petrol alive .. last time i used Fuel Fit in with my Petrol left standing for 8 months all was well when i restarted the engine.

[Andrew1967]

The S normally starts (reluctantly) on the old fuel but to be sure, I add a gallon of fresh fuel before turning the ignition on so its mixed in the tank and the pump draws the mixed fuel through initially.

Then a trip to the garage for a little more.

Draining is probably the best option though and then you have some fuel for the lawn mower or as Norman says, weed control

Whilst on the fuel topic, I have got the local Parker (Gates) rep looking into getting some E10 compliant 1/4" OD fuel hose, not 6mm, which is what the majority of stuff is on eBay but advertised as 1/4. It's not braided but I have obtained some (I think) zinc coated copper braiding from electrical cabling that is stripped and binned at work. Also some stainless. Should look good.

[AndyPen]

I always disconnect the carb pipe and run a line to a container to collect the first and most water laden fuel from the bottom of the tank - running the pump. Then I add a gallon of fresh fuel before trying to start. It is amazing what comes out, so use a transparent container once in a while and you can see first hand.

[Catmint]

I tend to just empty the carb dash pots of the old stuff and put fresh in and then add a gallon to the tank and it tends to go OK I second the briggs and stratton stuff - has lasted two years now and it still started 1st time

[snoopy64]

Hi, I know this comes up from time to time but I must admit my humble Cooper starts on any old stuff after the winter, as long as the battery good it starts and then it’s off to get some fresh in...