Yamaha T8 no idle (Rodbolt)

[pike hunter]

I have a T8 2001 that was running perfectly until the end of last season. Yesterday I went fishing and wasn't able to troll.

The motor idle then suddently the RPM goes up and after 5-10 seconds it slows down then rev-up again; so on and so on.

Carburetor, electronics?

 

[Mas]

Re: Yamaha T8 no idle (Rodbolt)

I would check plugs..one might be on the cusp of fouling?

MAS

 

[pike hunter]

Re: Yamaha T8 no idle (Rodbolt)

Already check.

RPM goes from 600 to 3000 then go back for 3-4 secs. High & low

Could it be the float or carb need a cleaning

It's a T8 LPTZ, 2001

 

[Mas]

Re: Yamaha T8 no idle (Rodbolt)

Do you have it throttled up and it drops down in rpms...or do you have it set at idle and rpms increase on their own?

Increase in rpm could be a lean condition and may be starving for fuel...but from 600-3000...that's a lot!

Carb float may be sticking and the bowl is running out of fuel..starving the motor. I would disassemble carb and check float, needle and seat for proper function and wear.

Electronics do not get worse then better then worse again...they just go downhill.

MAS

 

[CatTwentyTwo]

Re: Yamaha T8 no idle (Rodbolt)

You didn't mention anything about gas, but I assume you are using fresh gas and not what was left over from last year.

 

[onewildwest]

Re: Yamaha T8 no idle (Rodbolt)

I struggled with the same thing with my T8. I had it serviced a couple times and worked great again - for awhile. Seems there the carb is especially sensitive to the ethanol in fuel these days. Even though I have a water filter and put marine additives in my tank I had issues.
You have unhook your fuel line at the end of the day and let the engine run the gas out of the bowl.
You may need to take it in to be cleaned and then start this.
read more here: http://www.walleyecentral.com/forums/showthread.php?t=114553