Outboard fuel

Athene V30

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I have a gallon and a half of petrol mixed with 2 stroke oil left from last season. The people who service my outboard (and the only means of propulsion when the wind dies) suggest using new fuel at the beginning of the season.

Any suggestions as to how to dispose of this fuel as I drive a diesel car and my wife won't let me have a bonfire!

Happy sailing!

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In an ideal world new fuel is best they are right because the butane and propane which is injected into the fuel gradually escapes.
This will make the engine more difficult to start, but don't discard it you could mix it at 10% with fresh fuel then you will notice no detrimental effect.
This will only make sense though if you use more that 15 gallon a season!

All the best.

Trevor


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Every year I have several gallons of 2 stroke left from the previous year, always use it and have never had any problems. Think if you leave it 2+ years problems arise.

Just use it.

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I use mine up in my 4 stroke lawn mower (!) It doesn't seem to mind but it is a Briggs and Stratton (i.e. very basic sidevalve brick outhouse) Engine - Don't think I'd try it in a Honda...
My old 2 stroke Merc 7.5 would refuse to start on fuel more than 6 months old so have always used fresh fuel at the start of each season

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Mix it in with the diesel , at 5%

there will be no problem, & fuel will wax at a lower temp as well.

<hr width=100% size=1>David
<A target="_blank" HREF=http://www.euroboating.net>http://www.euroboating.net</A>
 
Winter grade diesel will not wax above -18 degrees centigrade, I know HGV drivers used to mix some paraffin with diesel when we had very cold winters years ago. The addition of petrol to diesel I have not heard of and must say I would not recommend it. As it will affect the flash point of the fuel and must also effect how the fuel works in the diesel engine.

Trevor
Ex Shell Laboratory.

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Petrol in diesel?

My last diesel car (a TDI) said in the manual (if I remember correctly), that should petrol get into the fuel tank as long as it could be diluted with diesel so that it was less than 30% by volume, everything would be OK. I imagine that the primary concern is the lubrication aspect of diesel more than flash point. Still, this isn't a recomendend approach.

Jeff.

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Whilst petrol does deteriorate on storage (you get long chain butyls forming) the degradation over a 6/12 month period would be unnoticeable.

I think your outboard folk are being ultra-cautious, I've always (in 22 years) happily used last years' mix with no ill-effects.

I would however draw the line at >3 year old fuel.

I'd certainly not risk using it in a diesel, especially a turbo-charged heavy oil engine, the antiknock agents now used are nearly as lethal as tetra-ethyl lead for CI engines.

Even fuel techies, only recommend the addition of straight gasoline as a last resort for anti-waxing in diesels at the rate of 1%.

If the worst comes to the worst you could always give it away to your local live-aboards for their outboard - they probably do their own OB servicing and don't have the siren voices of "mechanics" whispering nonsense in their ears.

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Re: Petrol in diesel?

Probably had a little rider as well that it shouldn't be lead-replacement petrol?

The problem, apart from lack of CI, is that you need to replace the fuel-lines, all sorts of nasties get dislodged and you have continuous fuel-starvation problems. after petrol in the system.

The only safe thing is to replace all the fuel-lines.

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There was a long thread on this subject started on 16/09/02 with some expert input from Nigel Luther. (a search for 'stale fuel' will find it)

As I said then I always store fuel in metal cans as i believe polyethylene may allow oxgen to diffuse in and maybe some of the lighter fractions to diffuse out they also exclude light. I also only keep full cans to minimise the amount of air in contact with the fuel and I always filter the fuel thru' a fine filter at the start of the next season. The only time I had trouble was when I didnt filter it. I have noticed the Seagull dosnt run so well on very stale fuel.

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Got the info out of a Mercedes Benz instruction book, for use in countries where the addition of parafin was not allowed for duty reasons, but defer to the greater knowledge of others. personally I would use it though, but perhaps at lower concentrations.

David
<A target="_blank" HREF=http://www.euroboating.net>http://www.euroboating.net</A>
 

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