Not used boat for two years - old fuel?

[Revenger715]

As per title, put boat away end of 2015 season with a full tank of fuel (98) with the intention to use it in 2016 but didn't find the time! It was however serviced in Spring 2016 at Evinrude dealer (she is running an Evinrude 150 Ficht) so motor was run up at that time.

Since then she's not been started at all. I've finally dug her out of hibernation (she is kept in a dry barn which has a nice current of air running through it which doesn't get humid/damp). Do we think she is good to go or should I drain the tank and refill. If so, how do I get the old fuel out??! And if I do use the current fuel what is the worst that can happen - run lumpy/kill the plugs?

Cheers, 715

[simonl]

Make sure you replace the water/fuel separator filters. Ideally have one with a visible bowl. Water can kill injection systems. Other than that I've used some pretty ancient fuel.
Make sure it still smells something like petrol though

[jeffstevens763@g]

put some conditioner in it and dilute with some new fuel should be fine

[Seaflyer02]

Originally Posted by jeffstevens763@g

put some conditioner in it and dilute with some new fuel should be fine

[Orwell boy]

I'm no chemist but I think I have read that the make up of the petrol which absorbs the fuel conditioner will have already be saturated from the heating and cooling of the surrounding seasons atmosphere so no point in adding more money ,this is only true if the tank is open to breathe which I suspect it will be , this is why fuel can keep in a plastic sealed can ok but not in your lawnmower , sometimes ther is a plus that most outboards are made to run on fuel availiable anywhere in the world and some of this is very low ron value so you won,t know till you try ,I think I would clean the carb up a bit first , these are my experiences not chemistry knowledge ,I personally have syphoned gallons of fuel out of boats especially mercruisers where the bus engine just wont run on poor fuel , my current Honda outboard seems much more ameniable

[jwalker]

Start it, if it runs well just use it.

[The Black Pig]

At the very least I would mix it with some new fuel, they're are plenty of post on old fuel here

[beamishken]

If it starts use it

[Jus]

I had a very similar question a few months back, with engine a 75 Etec and fuel a year old. I did quite a bit of research and there seemed to be a lot of advice against using any kind of old fuel in these motors for fear of damaging the injectors. In the end I went on the side of caution and drained the tank off, kept the old fuel and used it for the lawn mower and car.
I drained it off by disconnecting the fuel pipe from the engine side of the primer bulb and attaching a hose to the bulb. I then hung this hose quite a bit lower than the boat into a can and used the bulb to start off the siphoning. Once flowing it kept going, even if slowly.

[jeffstevens763@g]

your car not fuel injected?

[Jus]

Originally Posted by jeffstevens763@g

your car not fuel injected?

Yes, it is but it is, but the injectors are a fraction of the cost of those on the Etec! Also the engine was brand new last year and is worth many times what the car in question is.

[jeffstevens763@g]

Originally Posted by Jus

Yes, it is but it is, but the injectors are a fraction of the cost of those on the Etec! Also the engine was brand new last year and is worth many times what the car in question is.

fair enough jus but if you use say lucas fuel stabilizer it keeps the fuel condition with the added benefit of cleans , maintains & lubricates carbs, pumps, injectors, & compression rings that way you protect all you engines.

[beamishken]

Has anyone actually had a problem with clean old fuel?
IE engine won't run or fuel does damage to an engine?
I don't mean damaged injectors because they sat with water in them for 18 months because the filtration wasn't up to it.
I mean a tank full of fuel that's a few years old with decent filtration where an engine won't run or is damaged which is directly attributable to the old fuel?
Let's see how many people have actually had a first hand problem
Frankly I think it's an urban myth but happy to be proved wrong

[jeffstevens763@g]

never in any engine i have owned 2 or 4 stroke.
1 always run tank low end of season or trip
2 always top up with new
3 always have good filtration
4 and now but not always done it, stabilise fuel end of season.

if you have a petrol car no issues just jiggle hose into tank

[Jus]

Originally Posted by jeffstevens763@g

fair enough jus but if you use say lucas fuel stabilizer it keeps the fuel condition with the added benefit of cleans , maintains & lubricates carbs, pumps, injectors, & compression rings that way you protect all you engines.

Yes, that's the plan for the end of this season

I would be interested too to hear if anyone had a real report of a serious engine issue directly caused by old fuel.

[HDAV]

If fuel was unstabilised 2 years ago I don't think adding stabiliser now will do much to help.

Either drain and buy fresh £110 or run it and risk it, in the grand scheme of operating costs it's not a lot compared to the cost of the motor or even a service.

[Erin]

I wouldn't worry unduly. I had a very similar situation in 2013/2014 when I didn't use my boat for over 18months with a near full tank and with the boat stored outside in a humid location. The fuel will have lost some of its potency but the engine fired up just fine and she ran with no perceptible difference the following season. I have a primary filter and the engine has it's own water separator. Neither showed any side effect.