8f only idles with choke adjusted

[jyoung]

I have a 2006 8hp high thrust. maybe has 75 hours on it. It has run great all season. This weekend it was hard to start and would not idle. I was able to get the rpms down by opening the throttle and choking the engine with this I was able to shift and run at idle. The motor runs like a champ at higher rpms. Just slalls if the rpms get in the 1500 to 1800 rpm area.
Any help most appreciated
Jon

[jonp]

Hello,

You may be dealing with an ethanol issue...Water. I would clean out the little bowl filter if you have one. Check it closely as this little bowl will also act act as a tiny water separator. Also drain the carb, should be drain plug or bolt on the bottom of the carb. You may not need to remove it completly to drain it. Hopefully the gas did not jell up, if so you may need more invasive carb work or try cleaning with a seafoam like product. I would also try adding an additve to the gas if you see signs of water in the bowl, Startron seems to be the popular one.

Good luck

Jon

[Hamfisted]

Some type of fuel restriction. Do you have a service manual for it? Post your email if you need one. There's a small fuel pump on the side of the carb but I would think your motor is too new to have a problem there but you never know. Could have just got some dirt or something else in the gas and it's found it's way to the carb and blocking a low speed jet or something. You can try pouring a can of Berryman's Chemtool (Walmart) in your fuel tank and running it through, see if that cleans it out.


-Mike

[sherwin]

Sounds like my problem with a T9.9. There are two
jets, high speed and idle on these carbs. They are very fine and tend to block up. Sounds like your idle jet has that problem. A mechanic showed me how to clean these jets with a very fine wire, like a strand from electrical wiring. Just poke it gently through. Worked for me. Only problem is that it keeps coming back. Talked to Yamaha customer service today and they had no solution for the blocked jets. Water in the tank or carbs would cause poor running, but should not inhibit starting. The problem may be Gasahol, but I haven't found an additive yet that will cure it ( Stabil, Sea Foam, Mercury Quick Clean).