10% ETHANOL

[Bob Miller]

I've noticed on my 04 Warrior that the fuel with 10% Ethanol in it does not run as good as the fuel with 100% gas! I did two trips to Maine this year and I'm running 165 main jets with 4 TPI valves, and in the past when I was running straight gas out of Quebec with the TPI valves all the way open, this engine would run very strong

During these trips to Maine with the 10% Ethanol blend I could not run with the TPI valves open because it would sputter and misfire in the midrange (5-8000 RPM) When I closed the TPI valves it would run better! The Ethanol blend was creating a lean condition, and I was able to test this by opening the Choke while it was sputtering and notice an improovement! When I got back from the trip I drained the gas tank and put some CT gas in it which also has Ethanol and it ran great! So I don't know what's going on with that gas from Maine but the machine definitely does not like it

 

[grader]

the regular gas here is 10% ethanol and so far no problems. the theoretical perfect mixture for straight gas is 14.7 to 1. gas with 10% ethanol the ratio drops to 14.13 to 1. i suspect you are fairly lean in the midrange if its misfiring. mine has run 16 plus to 1 in midrange with no problems, but i have since jetted up. you might also gain performance jetting up from that lean. now that i have an a/f gauge the guesswork is not needed.

 

[Bullet69]

We've had 10% ethanol in Mn. for years. My 05 RX-1 hasn't had any problems running it other than you have to clean the carbs if it sits for a while.

 

[Bob Miller]

It's interesting to note that Yamaha states in the Owners Manual
"Do Not Run More Than A 5% Ethanol Blend"
By the way mine ran on this 10% blend which also might have been somewhat stale, I can see why they make this statement!

 

[Sled Dog]

I've noticed on my 04 Warrior that the fuel with 10% Ethanol in it does not run as good as the fuel with 100% gas! I did two trips to Maine this year and I'm running 165 main jets with 4 TPI valves, and in the past when I was running straight gas out of Quebec with the TPI valves all the way open, this engine would run very strong

During these trips to Maine with the 10% Ethanol blend I could not run with the TPI valves open because it would sputter and misfire in the midrange (5-8000 RPM) When I closed the TPI valves it would run better! The Ethanol blend was creating a lean condition, and I was able to test this by opening the Choke while it was sputtering and notice an improovement! When I got back from the trip I drained the gas tank and put some CT gas in it which also has Ethanol and it ran great! So I don't know what's going on with that gas from Maine but the machine definitely does not like it

I think you need to clean your jets mine was doing exactly what you describing. Clean all three of them and your problem will go away.

 

[Bob Miller]

Before draining the tank I pulled the carbs apart and they where clean as a whistle, all jets where clean,I put it back together and it still ran like crap
It wasn't until I drained the gas tank and replaced the gas that it started running good again

 

[Sled Dog]

The power jets on mine looked clean as well but there was clear smooth stuff caked on them. I needed to scratch it off with a wooden toothpick so look carefully. Once I did that my midrange no power was gone for good.

 

[Bob Miller]

I cleaned all the jets with compressed air, but I held them all up to the light before blowing them out and they where clean. Like I said this did not make ANY difference
It wasn't until I drained the gas completely and put new gas in it that it started running good again