3.5 hp does not want to idle

[smsscuba]

My 2008 Tohatsu 3.5 four stroke outboard (MFS3.5) stalls if let run on very slow idle.What can I do to stop this. The plug is new, carb slow idle jet was removed and cleaned.

 

[pvanv]

Re: 3.5 hp does not want to idle

Clean the carb again, properly, and set the idle with a good shop tach. That carb does not have a slow idle jet, so what was removed/cleaned?

 

[jrs_diesel]

Re: 3.5 hp does not want to idle

If it's anything like my 3.5 2 stroke, there's only one jet, the main jet. The only adjustment is for the idle speed.

It's also happens to be my favorite carb to clean or service because of it's simplicity.

 

[smsscuba]

Re: 3.5 hp does not want to idle

ok, so i must have cleaned the main jet, it was partially blocked though.Which screw is intended for the idling setting? Many thanks in advance.

 

[Sea Rider]

Re: 3.5 hp does not want to idle

You will only find one screw on the carb, turn CW to increase rpm, adjust to a point that when engine is in gear at idle, engine does not die.

Happy Boating

 

[pvanv]

Re: 3.5 hp does not want to idle

ok, so i must have cleaned the main jet, it was partially blocked though.Which screw is intended for the idling setting? Many thanks in advance.

Did you do a complete disassembly and 4-hour soak in real carb dip, such as Tyme, followed by a warm water wash-out and a good blow out (either with compressed air or carb spray)? If not, you probably still have varnishing in the low-speed circuit. Especially since you found junk in the main jet. After you are 100% sure that you have really done a very thorough job on the carb, reassemble everything, and then adjust the warm idle per the specs in the Factory service manual, using a good shop tach. If you still can't achieve a slow enough idle, and everything else (including the spark plug) is in perfect condition, the carb may to be replaced.