Aspen Fuel - Small Outboard

Helidan

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Just picked up a new Suzuki 2.5 for the tender, was going to buy another electric outboard but decided to go back to petrol power.

Anyway, was wondering whether it is better to use E5 super unleaded perhaps with a drop of Starbrite Star Tron added or give Aspen a try?

Fuel cost is largely irrelevant, I just want to ensure reliability as much as possible.
 
If the outboard is in regular use then E5 with starbrite should be fine. It seems to be the little used ones that are the problem. Well that's my experience.
The outboard will see very light use - mostly short runs from the pontoon to our mooring.
 
The outboard will see very light use - mostly short runs from the pontoon to our mooring.

So typical small outboard use ......

Just make sure you turn off fuel - let engine stop because fuel starvation ... unless you are going to restart engine shortly after.

I got to the point that I could gauge when to close fuel valve before arriving at mooring / shore to reduce waiting time for engine to stop.
 
I use Aspen in all my lightly used petrol engines, in the garden and in my o/b, 2 stroke and 4 stroke. As you o/b is new I assume it’s 4 stroke, but just in case be aware that Aspen specifically warn against using their 2 stroke fuel in a marine environment and recommend mixing their 4 stroke with marine 2 stroke oil.
 
I changed to aspen on recommendations of other yachties using their outboards on dinghies , I have been very pleased , easy starts , left in over winter , no gumming up and started second pull . Also it doesn’t smell of petrol or petrol fumes . Makes Mrs B happier
this is on a four stroke 3.5hp outboard.
 
For the last year I've used E5 petrol with the Honda additive. Been ok for both 4t 2.3 outboard & 4.5 lawnmower, 2t strimmer & small generator.
 
Since switching to Aspen not had any problems - o/b starts easily even after leaving for months and no issues if you forget to use up fuel in the carb. For peace of mind the small extra cost is well worth it if o/b only used occasionally.
 
Just picked up a new Suzuki 2.5 for the tender, was going to buy another electric outboard but decided to go back to petrol power.

Anyway, was wondering whether it is better to use E5 super unleaded perhaps with a drop of Starbrite Star Tron added or give Aspen a try?

Fuel cost is largely irrelevant, I just want to ensure reliability as much as possible.

For as long as I can remember Esso Synergy Supreme 99 has been *zero* ethanol in most Southern Garages which has been great:

Synergy Fuels | Esso

Unfortunately that ends in Sept '23, so not so great. At least your last five litres can probably be zero ethanol.
 
I only use it in a chainsaw that sits for up to a year sometimes with no way of draining carb, always goes straight off unlike when I used regular petrol, I know of a few bikers that use it at the end of summer to keep fuel system gremlins away next spring.

I always run my chainsaw till tank is empty if I am leaving it for long period. I only use the stop switch for short stops ...
 
Strong recommendation for Aspen 2 for two stroke and Aspen 4 for four stroke. No gumming, starts easily, runs well, worth every penny
Been using for years, would never go back.
 
For as long as I can remember Esso Synergy Supreme 99 has been *zero* ethanol in most Southern Garages which has been great:

Synergy Fuels | Esso

Unfortunately that ends in Sept '23, so not so great. At least your last five litres can probably be zero ethanol.

Esso made hay on this one ... while in fact most petrol of 97 and up was Ethanol free till very recent.
 
I changed to aspen on recommendations of other yachties using their outboards on dinghies , I have been very pleased , easy starts , left in over winter , no gumming up and started second pull . Also it doesn’t smell of petrol or petrol fumes . Makes Mrs B happier
this is on a four stroke 3.5hp outboard.

Similar experience with Aspen.
Mariner 2.5 2-stroke
 
Using E10 fuel seems to have been the cause of problems with both mine and my berth neighbour's Mariner/Mercury 6HPs; some kind of white residue building in the float chamber and forming small particles which prevent the needle valve fully closing.
Running the engine dry still leaves about 10mm of fuel in the float chamber and didn't help.
There's no local source of alkylate fuel and no E0 fuel emanates from the Grangemouth refinery so I've taken to removing the ethanol using the 'add water and shake' method much publicised on Youtube. I run E10 or whatever in the external tank and then switch to the internal tank of E0 and run this through before stopping and have had no problems since.
By the way, readily available Tesco Momentum petrol is actually E3.5 and at 99 octane is a good base for ethanol removal as the process lowers the octane rating slightly.

I've not had any problems running E10 on 2 stroke machines of any sort; perhaps the addition of 2S oil or the constant pumped re-circulation of fuel through carb chamber and tank make them less susceptible.
 
By the way, readily available Tesco Momentum petrol is actually E3.5 and at 99 octane is a good base for ethanol removal as the process lowers the octane rating slightly.

Thanks for the tip. Where do you find out the actual ethanol values as opposed to the E5 etc?

Like you I've had no problems with my 2T engines despite leaving fuel around for years at a time but then I've had no problems with 4T engines including motorcycles that have been left standing for 6 years and started as normal with the fuel there were put away with. Despite that I'm keen to avoid ethanol and stale fuel as much as I possibly can so I never have the problem.
 
Thanks for the tip. Where do you find out the actual ethanol values as opposed to the E5 etc?

As part of the ethanol removal process, using measured quantities of fuel and water, you get to see how much ethanol there was in the fuel.
 
Thanks for the informative replies, I've now purchased 5L of Aspen-4 which should last me a good while. Luckily I've got a local stockist. I'll report back in due course how I get on with it.
 
As part of the ethanol removal process, using measured quantities of fuel and water, you get to see how much ethanol there was in the fuel.

Ahhh, you actually measured it! Thanks.

Looks like I'll be using Tesco Momentum from October.
 
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