ethanol/ fuel line question

[jimf232]

Can anyone tell me (for sure) if the fuel lines between the fuel pumps and the carburetors on the 1990 yamaha 150's are ethanol compatable. I've been having issues with sticking floats and needles requiring cleaning/rebuilding 2 or 3 times per season X2 (twins). Everything including the tank has been replaced to the fuel pumps. Can not figure out what is causing this problem!

Suggestions welcomed!
Thanks,

 

[99yam40]

Re: ethanol/ fuel line question

Have you replaced the needles and seats or do you just keep cleaning them?
Not real sure but I do not think ethanol fuel was around back then so they may not be and the needles may have a problem with it too.

Most of the time if this is happening after a fairly long sitting spell and you have stabilized fuel in the system and good oil then you may need to drain the carb bowls to keep the needle open while sitting.

 

[jimf232]

Re: ethanol/ fuel line question

I do a complete clean and rebuild on all 3 carbs (seats are not replacable). As for the the sitting spell, this will occur after three weeks of not running the boat. Could it be that the gas in the carbs is evaporating leaving some sort of sticky residue behind stopping the float travel to seat the needles? What I'm seeing is gas pouring out of the carburetors. After the rebuilds, the motors run like champs.
The question is, are the fuel lines breaking down from the ethanol causing the residue or is this just another negitive effect of ethanol fuel?
Fuel is stabilized with Startron at each fill up and 10 micron filters are in line with each motor.

 

[99yam40]

Re: ethanol/ fuel line question

Does not sound like sticking needles as that is where the needle sticks in the seat and you can not get fuel into the bowls. Have you found trash in the bowls or seats when this happens?

May be best to replace lines and/or floats to see if it helps if you can not identify what is holding floats and needles from doing their job

 

[jimf232]

Re: ethanol/ fuel line question

You are correct, the needles are not making it to the seats allowing the carbs to fill with fuel. Obviously the floats sticking are the culprits, maybe another good cleaning and running the motors more often will correct this problem since this does not occure when boat is run weekly.
Oh,no trash found in bowls.
Thanks for the responce.

 

[SparkieBoat]

Re: ethanol/ fuel line question

welcome to the wonderful world of 10% ethenol...imagine how great 15% will be...wooohooo