stale fuel ? how long till petrol is gone off?

[steveo3002]

not related to my ford focus ramblings

ive had a car parked up 9 months , plus the fuel was already in there so 10-11 month old fuel

started it up for its mot and it idles ok but misfires at revs /load

does this sound like it might just be the fuel starting to go bad ? this car is away from home so havent had the tools with me to check over anything other than the dizzy cap

 

[123hotchef]

whos knows to be sure mate can u run it from a can of fresh fuel

 

[dobbslc]

Modern petrol is *****! Tescos worse stlll.
In a bike tank 6 months is enough for it to go off.
I'd top up with new fuel and change the plugs.

Mod edit: language

 

[steveo3002]

hmmm its usualy stood 6 month and i get away with it , wondering if thats just too long

do you think brimming it from just under 1/4 would make it good enough ...dont really wana drain it

 

[123hotchef]

yeh ifit is just fuel

 

[123hotchef]

try syphoning the worst of it out if u can

 

[rtbcomp]

I've had my car off the road for 3 years and it started 2nd pull on the switch.

 

[Wendelspanswick]

I do think that the increase in biofuel in modern petrol does lead to a deterioration but not to the extent some people would have you believe.
More likely that sediment has settled in the cards or corrosion on the points if it's a traditional ignition system.

 

[Chris Stevens]

Phase separation is a problem with Efuels, and this leads to water settling at the bottom of the tank. Causes all sorts of issues, but doesnt seem to happen all the time. To be safe drain the fuel, and if it looks at all dodgy change the fuel filters as well as new fuel.

 

[Screwdriver]

I once bought a bike that had been stood in a garage for ten years. The fuel was like napthalene (mothballs). That was an exceptional case and it got recycled into cleaning duties. Didn't half stink mind!

On the other hand I picked up a (crashed)bike the other day that had been stuck in a garden for two years. Fuel smells good, probably stick it in the van or strimmer/chainsaw.

Not familiar with modern fuel mixes separating but I will look out for it.

Otherwise: use your nose.

S.

 

[brightspark]

Not just wouldn't make an engine run, wouldn't burn, at all, even a bit, even a rag dipped in it and held over a match wouldn't light

...
Old fashioned fuel was much more fun.

that's incredible don't over do it

 

[Bullet2012]

I believe that the increase in ethanol in petrol causes issues, ethanol attracts water and as we all know currently water is not a suitable fuel for IC engines.
Can you siphon off some fuel into a clear glass container and then observe if it separates into "petrol" and water ?

 

[gaz1]

ive got a cultivator that i start up yearly as sometimes cant be bothered draining it

sometimes its a swine to start has been known to pull some crap up the system the last fueling it had was over 2 years + ago and ive just used the last bit in the tank other day just still had the smell of petrol so topped it up with some new as had to get 5 gallon of it 6.00 worth

cultivators engine is briggs and straton 4 stroke 5.5 works ok with it

 

[sardine]

Something like a mower wont start on stale fuel, but once its running you can feed it 50/50 with fresh fuel, and use it up, as long as its only months not years old.

 

[wookie]

I think a lot depends on the engine, I have a WW2 jeep that starts and runs fine on seriously old/stale fuel (well over 12 months old), but if I remember correctly it was designed with only 68 octane fuel in mind, my chainsaw, strimmer & mower don't like stale fuel so if they won't start I usually drain them and refill with fresh, the stuff I drained off then gets chucked in the jeeps tank (waste not want not).

 

[Wedg1e]

I drained the tanks on my TVR to repair a pinhole and it ended up being two years before I put it back together. Initially I intended to use the old fuel (about 15L of it) just to leak test the system as I'd replaced all the hoses etc. but of course I started it... and then took it for a drive... and it was fine.

 

[Robotstar5]

I recently bought a service kit for the ride-on mower and there was a bottle of fuel fit included, supposed to stabilise the fuel up to 3 years?

 

[Lufbramatt]

Just finished using up the 60 litres of 8 month old petrol I took out of my BMW, my old Passat ran fine on it but I stuck it in 20 litres at a time so it was mixed in with fresh fuel.

 

[steveo3002]

Just finished using up the 60 litres of 8 month old petrol I took out of my BMW, my old Passat ran fine on it but I stuck it in 20 litres at a time so it was mixed in with fresh fuel.

did it look /smell like fresh stuff ?

 

[normspanners]

A guy I know works in the forestry and they will not have fuel for longer than a couple of weeks because they say they can tell the difference with the chain saws, in the way they perform but worst thing was the starting with stale fuel.