2007 3.5 HP 4-stroke idle issues

[avia8tur]

I've seen similar posts but can't seem to find the answer. My engine ran great for the first year as a tender to our cruiser. Half way through the second season, the engine started hard and would not idle unless the choke was ON and it will not accelerate all that well. Choke is needed almost constantly. I've used additive for the ethanol, cleaned the gas tank and used new gas, removed and cleaned the carb several times. Still no luck. I noticed after running the engine in a tank that there was substantial sludge floating however I think that is due to the cleaners and gas treatment.

I've considered a carb kit, needle valves or even a new carb. Does anyone know if there is a idle mixture adjustment? There doesn't seem to be any adjustment available as the jets seem fixed.

Suggestions??

 

[TOHATSU GURU]

Re: 2007 3.5 HP 4-stroke idle issues

There is no need to adjust the mixture...Only a need to correctly clean the carburetor. You have to dip the carb in a pail of carburetor cleaner for three hours.

 

[avia8tur]

Re: 2007 3.5 HP 4-stroke idle issues

Thank you very much. I disassemble the carb and submerged it overnight. You said 3 hours but hey, overnight has got to be better right? (rhetorical). I reassembled the carb and it ran rough, not much change. However, I let it run for a half hour at high idle and the problem is much better. Remember, it wouldn't idle at all so high idle was an improvement. It is now idling much better, and the problem appears to be solved....for the most part. I'll keep you all posted.

Tohatsu...thank you for your input.