2 Great articles about ethanol and older motor

[Skydive80]

I found these articles researching another issue but found a lot of the information important (1969 Merc 650) and figured I would pass them along.

http://www.used-boats-canada.ca/item/ethanol-blended-fuel-and-boat-engines
http://www.used-boats-canada.ca/files/important_news_for_boat_owners.pdf

I hope these might help preserve some of the older motors out there.

SKydive80

 

[j_martin]

Re: 2 Great articles about ethanol and older motor

A little mis-information there, at least on the vapor lock issue. Ethanol doesn't boil at 88 F, but nearer to 88 C, or about 190 F. The problem is that the ethanol has a very high octane, and early blends of E10 used very cheap low octane fillers, bringing it down to about 105. Some of those components had a very high vapor pressure (low boiling point) and that is what caused the vapor lock.

It didn't take long for the regulators to discover the high vapor pressure with it's tendency to cause hydrocarbon pollution, and now regulate a maximum vapor pressure. The blend may vary with the season in some juristictions. Summer gas is always low vapor pressure. Winter gas in very cold places may be allowed to have higher vapor pressure to help engine cold starting.

Best bet if it's sold where you are is to run off-road (non-oxygenated) fuel.

hope it helps
John