Fuel Going Off ?????

[Raesen]

Hi all

With all the rain about for the past month or so it has been difficult to get out in the boat for some time.

I believe that fuel in containers/tanks has a "shelf" life shall we say and was wondering how old is too old for fuel to be left in the tank and then used??

Weeks, months, years????

Also is there an additive that prolongs the time that unused fuel can be stored before actual use without having an adverse affect on the condition of the motor.

I am sure there are some mechanics and/or experts out there who can help me out with these questions.

Cheers and thanks in advance
Pete

[FNQCairns]

The area is largely one based on personal opinion irrespective of technical best practice.

Will come down to what temperature the fuel was stored, it's lack of access to free air...then individual aspects like the engine it is to be used in, premix, how the engine is to be treated.

Bottom line is there is no single recipe will suit all in all circumstance and almost no recipe that can get around the technical best practice side of issue.

Years are most certainly out, a couple months doesn't have to be depending on the individual circumstance of the stored fuel and it's end use.

Weeks as opposed to a month can in many instances be OK, a few will still get caught out as thats the nature of the beast.

Fuel conditioners work if used at the very first instance the fuel is stored...in effect it works just like but not half as well as storing fuel in a full and sealed container to limit all diffusion and full oxidization.

Short of the above what are the specific details? one can then at least within a fair margin of safety hazard a semi educated guess.

cheers

[Triple]

http://www.sta-bil.com.au/

http://www.fueldoctors.com/tech_talk/how_does_fuel_doctor_work_/

[marto78]

Ive had a tin of 2 stroke fuel sitting for about 7 or 8 months which I use in the mower and it only became unusable last week (the mower kept conking out). The fuel in my boat will sometimes sit for a good 2 or 3 months without use but I usually top it up with 50l of fresh fuel when I head out and have never had any dramas (touch wood). Thats just my personal experience it might be different with your boat.
cheers marto

[Scalem]

Stay away from anything with ethanol for the boat.

Some people beleive that topping up with premium fuel will improve things, but common sense should tell you that if the top up fuel goes into a tank that is more than 50% full of old fuel ( older than 6 months is my benchmark for what I consider old, my opinion only) then you are still likely to not acheive much by topping up.

This information comes from a leading service agent/ mechanic in Brisbane when we were trying to diagnose a problem I was having with my outboard. Try to run close to empty in your main tank occasionally, having an auxiliary tank on standbye with enough fresh fuel to get you home if you were in doubt. I run two fuel lines into the fuel filter which is easy to do because most filters have two intakes. Have an in line tap installed on the main line on the fuel filter, which will divert to the spare tank when turned off. You should never openly pour fuel from an external source such as a jerry can while out to sea.

Scalem