Can 4 stroke outboard engines take E10 petrol?

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eddystone

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Consequences of incompatibility would include degrading seals in fuel line leading to fire risk
My personal interest is a 2.3 Honda probably 10 years old (ish)
Are new 4 stroke outboards E10 compatible?
 
eddystone said:
Consequences of incompatibility would include degrading seals in fuel line leading to fire risk
My personal interest is a 2.3 Honda probably 10 years old (ish)
Are new 4 stroke outboards E10 compatible?
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The owners manual I am looking at, for BF2.3D serial numberBAVJ-1000001 through 9999999 says no more than 10% ethanol
Check the manual for your engine if that does not cover it
 
I enquired to Tohatsu about E10 a few years ago and they were faintly encouraging about E5 but distinctly vague about E10. Lots of use of the word could, should,perhaps etc. I will try and find the response-it read very much like a legal disclaimer i.e. wanted to say E10 is ok but would not wish to be bound by that statement. My query was relating to a 2012 Tohatsu 20hp engine, normally aspirated not FI.
 
You should be fine....remember to drain or run the carb out of fuel prior to storage. I have seen reliability issues on Honda 2.3hp outboards after running on Aspen a number of times but 10% Ethanol should be ok
 
My BF6, about 10 years old, hates ordinary ( 10% bio ) unleaded. Fine the day it goes in, but if left for any time the idle goes bad and I need to clean the carb. Been ok on super though
 
RumPunch said:
My BF6, about 10 years old, hates ordinary ( 10% bio ) unleaded. Fine the day it goes in, but if left for any time the idle goes bad and I need to clean the carb. Been ok on super though
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Interesting that as I had to have a new carb on my 20hp engine at only 5 years old which I had always run out of fuel before storage. It had hard white deposits in the many little channels in the carb. You cannot get Super grade fuel on marine fuel pontoons, a pity.
 
I have been using the posh unleaded for some time. Costs a bit more but I don't use that much.

Copied from the web :-

BP Ultimate (super unleaded petrol) does not have ethanol added except in the South West of England. ... Texaco Super Unleaded petrol does not contain ethanol. Total: Ethanol is not added to any Total fuel (including standard unleaded petrol) except in the North West and South East of England.

Esso
Our Synergy Supreme+ 99 petrol has more cleaning power than our regular petrol – and includes molecules whose job it is to reduce the friction in your engine helping the moving parts work more efficiently.*
Although our pumps have E5 labels on them, our Synergy Supreme+ 99 is actually ethanol free (except, due to technical supply reasons, in Devon, Cornwall, the Teesside area, Scotland and NW England). Legislation requires us to place these E5 labels on pumps that dispense unleaded petrol with ‘up to 5% ethanol’, including those that contain no ethanol, which is why we display them on our Synergy Supreme+ 99 pumps.
There’s currently no requirement for renewable fuel, like ethanol, to be present in super unleaded petrol although this could change in the future, in which case we would comply with any new legislation.
 
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Just seen a consultation from the Dept of Transport. E5 petrol will still be available via the "super" grades, it is the standard 95 octane premium grade which will be E10. For supply reasons some petrol sold in remote areas such as the Scottish Islands may have no bioethanol added, Similarly some of the fuel terminals do not, at present, have the ability to blend in ethanol and will be allowed to supply petrol without adding ethanol.
The argument is that recent cars are designed to be compatible with E10, and the older cars are now reaching the end of their life. The consultation documemt I have seen does not mention non-road uses, I wonder how many old outboards are still running, or garden equipment such as lawnmowers and chainsaws.
 
The manual (copyright 1987) for my very old Honda BF15 says 'Do not use gasohol that contains more than 10% ethanol". I would therefore guess that most Honda outboards are OK with E10
 
There is a Honda Marine Advisory paper somewhere on the web -cannot find again - which warns against the instability of petrol with a biofuel element.
If you are having trouble with a Tohatsu 4 stroke ,particuiarly one with infrequent use,as I did ,try Starbrite 'Startron' enzyme additive .Worked wonders for me.Widely available and a bottle will last for years.
 
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