Ethanol in petrol

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sparkie

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Hi all, has anyone else had problems with their outboard's carburettor this year? I've been plagued with jet blockages all season. Mostly seems to be small black particles, which can't be from the tank 'cos I've got a decent car-type filter in the hood. I'm beginning to think that the rubber fuel pipe is disintegrating inside, and that this may be due to the increased ethanol in the fuel this year. Any suggestions?? Driving me mad!
 
sparkie said:
Hi all, has anyone else had problems with their outboard's carburettor this year? I've been plagued with jet blockages all season. Mostly seems to be small black particles, which can't be from the tank 'cos I've got a decent car-type filter in the hood. I'm beginning to think that the rubber fuel pipe is disintegrating inside, and that this may be due to the increased ethanol in the fuel this year. Any suggestions?? Driving me mad!
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If its an oldish outboard with hoses that are not ethanol resistant that could well be your problem

Replacing the hoses with modern ethanol resistant ones will hopefully solve that problem whether its ia actually due to ethanol or just age but you should also consider the possibility that the fuel pump diaphragm may also not be ethanol resistant.

Difficult to be sure without knowing the ethanol content of the fuel you are using but its a well know problem in those parts of the planet where high ethanol fuels are used.
Advice generally ranges from one extreme, replace all old hoses, diaphragms etc, to the other, do nothing unless/until you have problems
 
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Hi Vic, very useful. It's a 5yr old Tohatsu, would have thought it was resistant, but looking at the manual it says that using ethanol fuels voids the warranty.... great if that's all you can get. I've thought about the pump, and my feeling at the moment is to insert a filter just after the pump, and make the final connection to the carb with a short length of clear plastic pipe, newly bought, so presumably resistant, if I can squeeze in another filter.
 
I have taken to storing my fuel in a dark box to keep sunlight out, which can cause condensation and cause the ethanol to settle below the petrol & cause problems.

BP ultimate contains no ethanol according to BP. Don't assume that is so for other Premium fuels, I wrote to them all asking they all said ethanol content, whereas BP specifically said not, so I buy thet now.
I also fuel through a water trap filter/funnel as well.


I 've had no trouble since applying all 3 lines of defence. I'm not sure which one is critical
 
More on the effects of Alcohol in petrol

3.13 on page 11

http://assets.dft.gov.uk/publication...tudyreport.pdf

Also

If an engine is run on alcohol instead of petrol jet size is increased due to I believe lower calorific value, so putting alcohol in petrol without up jetting will lean the mixture, never mind the item above.

This page is quite interesting as well


http://ttypes.org/ttt2/ethanol-blended-fuels


and here for ...Modern cars with a closed-loop fuel control system can compensate the leaning effect of oxygen containing gasoline

http://www.iea-amf.org/content/fuel_..._compatibility

along wit the corrosive effects of e10,


and
http://www.whatcar.com/car-news/new-...orists/1229022


We really are being fobbed of with inferior expensive fuels along with emission systems that dont do the job judged by Boris latest offerings.

The expense of euro 4 & 5 for trucks has been a failure for cleaner air in London.
 
chewi said:
.....
BP ultimate contains no ethanol according to BP. Don't assume that is so for other Premium fuels, I wrote to them all asking they all said ethanol content, whereas BP specifically said not, so I buy thet now.
I also fuel through a water trap filter/funnel as well.


I 've had no trouble since applying all 3 lines of defence. I'm not sure which one is critical
Click to expand...
Good info - thanks for posting
 
And finally (putting the the original question aside as having been already satisfactorily answered), recent research here on our 10%-ethanol petrol available for cars concluded that while it was cheaper per litre to buy from the pump than straight unleaded petrol, its comparative lack in efficiency as a fuel made it a more expensive alternative overall.

Mike
 
I now always buy the premium unleaded that costs extra at the pumps for my outboards and garden machinery as I have heard that this contains less, (or even no) ethanol
 
dartmoor said:
I now always buy the premium unleaded that costs extra at the pumps for my outboards and garden machinery as I have heard that this contains less, (or even no) ethanol
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Don't assume that.
Only BP told me that there was no ethanol (in their BPultimate).
All the others that replied told me how much there was.
 
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