Tender fuel - opinions sought

snowbird30ds

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Has anyone used aspen fuel in a low useage small outboard motor? I have a suzuki 2.5 that is very rarely dragged out and used and usually not for very long runs so I was pondering over using aspen fuel instead of regular fuel, downside is £4 a litre but 3-5 years shelf life and not having to drain it every time makes it sound worthwhile as stale fuel is normally the biggest problem.
Not a good idea for a regularly used larger motor purely on cost but for the smaller rarely used motor it seems a good idea to me.
Can anyone give a genuine testimonial that does not come from a sellers website as they are always going to sing it's praises.
https://aspenfuel.co.uk/uses/
 
You still should drain it from the carb, as the volatiles will evaporate. It's basic physics. The advantage is the absence of any bio fuel.

You can achieve the same by going to premium petrol from e.g. Shell or BP, and adding a petrol conditioner such as Briggs and Straton "Fuel Fit". This preserves the gaskets and plastic fuel pipes as well as having good anti-corrosion and detergent properties. I use the above in chain saws, strimmers, hedge trimmers, generators (and the outboard). So a mixture of 2 and 4 stroke engines, and would not use anything else for fuel.
 
Yes, I have. I thought it would be great, albeit expensive, for the exact same reasons you cite.

But it proved a disaster! I have a Mercury 3.3 2-stroke so I bough the ready-mixed 50:1 2-stroke version of Aspen. On the first fill with only the Aspen pre-mixed fuel, after about 1 minute runing there was an almighty bang and the engine stopped dead. To cut the story short, it turned out to be the piston-ring which had snapped. To be fair to Aspen, they advise that outboards need a different 2-stroke oil, but a small, low-stress, one would be ok I had thought. I wrote a thread on it at the time: http://www.ybw.com/forums/showthread.php?390594-Alkylate-petrol-for-outboards
 
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Draining the carb and tipping out the old fuel usually works for me, but I guess if you can get away without doing that 5 min job using special fuel then it might be worth it. Issues often is water in the fuel and I'm not sure special fuel will be immune to that.
 
Issues often is water in the fuel and I'm not sure special fuel will be immune to that.

Aspen's website claims the stuff contains no ethanol, the principle culprit in the widespread issue of water contamination of fuel in recent years. (Ethanol is hygroscopic.) That said, I'm not inclined to use the stuff myself.

The name's a little unfortunate, if apt in a way the makers perhaps didn't intend; in the US, "Aspen" is a byword for expensive. A $100 bill is known there as an "Aspen 10".
 
Aspen's website claims the stuff contains no ethanol, the principle culprit in the widespread issue of water contamination of fuel in recent years. (Ethanol is hygroscopic.) That said, I'm not inclined to use the stuff myself.

The name's a little unfortunate, if apt in a way the makers perhaps didn't intend; in the US, "Aspen" is a byword for expensive. A $100 bill is known there as an "Aspen 10".

Aspen, Colorado is an exclusive ski area. In the 70s $10 would buy dinner most places, but not in Aspen. It's kind of a skier joke, like "boat buck" for $1000; not widespread.

The best cure for water in the gasoline is to CLOSE THE VENT every time you use it. Works perfectly.

I did a bunch of testing for a different magazine and learned that Mercury makes some excellent ethanol gasoline additives. Also Biobor EB. Others are probably not available in UK. The US has had E10 longer (now moving to E15 it seems), so we've had longer to work it out.

I've have zero problems with ethanol, across many outboards, and I've never drained a carb. But I have learned to close the vent and use Biobor EB. For fixed tanks, a silica gel vent filter really works.
http://sail-delmarva.blogspot.com/2012/11/gasoline-and-fuel-tank-vent-filters.html
http://sail-delmarva.blogspot.com/2017/05/100-best-buys-chapter-3.html

So no, I don't see value in overpriced non-ethanol fuel. They sell it here too (US).
 
Has anyone used aspen fuel in a low useage small outboard motor? I have a suzuki 2.5 that is very rarely dragged out and used and usually not for very long runs so I was pondering over using aspen fuel instead of regular fuel, downside is £4 a litre but 3-5 years shelf life and not having to drain it every time makes it sound worthwhile as stale fuel is normally the biggest problem.
Not a good idea for a regularly used larger motor purely on cost but for the smaller rarely used motor it seems a good idea to me.
Can anyone give a genuine testimonial that does not come from a sellers website as they are always going to sing it's praises.
https://aspenfuel.co.uk/uses/

I don't think you'll get much shelf life from the bit of fuel that's in the float bowl.
Nobody needs 3 years shelf life, you want to be using fuel reliably a few months down the line, that's all.

Whatever fuel you use, water gets into outboard carbs. Condensation I suppose. It is essential to either be able to drain the carb mid river, or carry a pair of oars.

I did go through a phase of using BP expensive go faster petrol for outboards, strimmer etc, but having moved house my local place no longer sells it, I've gone back to plain old unleaded with no issues. I do make an effort to keep fuel sealed as much as possible and don't buy more than I'll use in a few months. I have strimmer which I empty after each use as the tank isn't sealed. That seems to help.
We have a RIB which runs on premix, so any suspect fuel is easily diluted and used up.
 
Why can’t you trust the OP to know how long he needs his/her fuel to last. You also can’t blame aspen for problems if you run ok the wrong oil.

I drain the carburatoron my aspen-run twostroke (yamaha 5C -87) as part of winterization. In general, it runs much better and has a smoother idle on Aspen. If I happen to run on regular fuel for too long or just before winterization the engine runs rough next year. I guess the fuel clogs the carb. A tank of aspen seems to cure it.

Most of all, aspen smells much nicer, almost like spirits. And the exhaust smells much much less.

I am not sure about the situation where you live but I have aspen on tap which is only 25% more expensive.

Try it, you’ll like it. But do use outboard oil, of course.
 
I filled my jerry can with the cheapest petrol at a local petrol station in Croatia in 2014 and have been gradually using it over the years since, in both the outboard and the portable generator. A few weeks ago I finally poured the last dregs into both the Suzuki 2.5 outboard and the Honda gennie. The both started and ran perfectly during our 3 week cruise.

I will need to refill the jerry can in a few weeks when we are back in Croatia. This time I should be able to eke the can out to 6 or 7 years as the solar panels are now relieving the gennie of some of it duties but, guess what, the Suzuki will still start first pull in 2025. :encouragement:

Richard
 
The best cure for water in the gasoline is to CLOSE THE VENT every time you use it. Works perfectly.

If I close the vent in the filler-cap of my Mercury 2.2hp outboard, it eventually stops!

Re Aspen fuel, I recently bought a 5l can of their standard 4-stroke, but am waiting until the current tankful of regular fuel is used up before trying it. As per Aspen’s advice, I intend to add marine-grade 2-stroke outboard oil in the usual ratio of 1:50. I don’t currently suffer from a gummed-up carb because I always stop the engine by closing the fuel-tap anyway before putting the engine away, and I’ll still do this with the Aspen fuel. The extra cost of the Aspen over regular fuel is nominal as I only tend to use about 5 litres a year - and getting rid of old 2-stroke fuel is a nuisance and a waste in itself.
 
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Suzuki 2.5, last filled up with Aspen 4 in April 2015.
Not used since 2015, not drained etc.
Took out of storage last week, tipped out fuel from tank and refilled with Aspen.
Started straight away but wouldn't develop power until idling for a few minutes.
I chose Aspen due to intermittent use and reports of problems with blocking jets on Suzuki 2.5.
I use it for small garden machines which have occasional use. I'll continue with it in the outboard.
 
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