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Main Area => General GS500 Discussion => Topic started by: the mole on October 27, 2008, 08:15:32 PM

Title: Carb problem, 10% ethanol fuel.
Post by: the mole on October 27, 2008, 08:15:32 PM
Today I had to fill with 10% ethanol fuel (91) and when I got home the bike stalled. Restarted OK but only on one cylinder, there was fuel leaking out the overflow hose. Problem was in the left carb, so I opened the drain and emptied it hoping it was just crap in the float needle. Runs OK again now, but has anyone had any damage to carb seals/o-rings from using ethanol?
I'm hoping it was just a coincidence.
Title: Re: Carb problem, 10% ethanol fuel.
Post by: lilwoody on October 28, 2008, 03:09:04 PM
REPLACE YOUR FUEL FILTER ASAP!!!! Try to find several 5 micron filters. My sons 250 Eliminator did something very similar and the fuel filter had literally went mushy (the ethonol started to dissolve it). His carbs were clogged completly but nothing a few hundred buck didn't cure. The alcohol will dissolve most sediments in your tank and will run them right through a 50 micron filter. On my boats I have had to go to 5 micron filters and went through 3 of them in the first 100 gallons of fuel. It's dropped the fuel ecomony on all of my vehicals 4 to 20%, my large boat being hit the hardest. It dropped from 2.5 to 2 mpg, this corn gas is pure crap. One other thing, if you live in a humid climate you can't let it sit for longer than 30 days because it will "phase seperate" (absorb water) and drop the octane rating down to the low 80s (this is utter death to a 2 stroke). Not to mention you have 10% of the volume of fuel now as water in the bottom of your tank. For boats this is a major pain.
Title: Re: Carb problem, 10% ethanol fuel.
Post by: ohgood on October 28, 2008, 04:32:50 PM
Quote from: the mole on October 27, 2008, 08:15:32 PM
Today I had to fill with 10% ethanol fuel (91) and when I got home the bike stalled. Restarted OK but only on one cylinder, there was fuel leaking out the overflow hose. Problem was in the left carb, so I opened the drain and emptied it hoping it was just crap in the float needle. Runs OK again now, but has anyone had any damage to carb seals/o-rings from using ethanol?
I'm hoping it was just a coincidence.

the 10% shouldn't hurt things. i filled up with that stuff many times while we lived in florida. i'd bet you got a combination of bad gas (watery crap), 10% ethanol, AND a stuck or partially stuck float needle.

add in a worn plug and you've got a crap running bike.

check your plug wires while you're at it. they'll make you think the carbs are gummed.


Title: Re: Carb problem, 10% ethanol fuel.
Post by: arbakken on October 28, 2008, 05:12:41 PM
i've never, ever filled up with anything BUT 10% ethanol on all of my bikes, and have NEVER had a problem with it
Title: Re: Carb problem, 10% ethanol fuel.
Post by: applecrew on October 28, 2008, 06:38:21 PM
 :cheers:
Here in SE PA, all fuels are 10% ethanol blend.  I've been running 91 octane for 6500 miles without incident.  Because I ride approx 350 miles a week, the stuff doesn't get a chance to sit around and absorb water.  I'll be very careful about this in the coming months as icy roads cut into my riding time :mad:.