T9.9 Carb thermal valve

[al kayser]

I have a cold starting problem. The motor will start when cold if I hold my finger over the air intake and run on high idle as it should. After the normal time motor comes to normal idle. It seems as though the thermal valve is working, but the carb doesn't get the choke affect. I have taken the valve apart and can't see a problem. Also I have dissembled the carb and cleaned in carb cleaner. All jets are clean.

Any help would be appreciated.

[boats.net]

It is usually plugged passages in carb or prime starter, might try to richen up the pilot screw a little.

[WET-BOX-MARINE]

what year

these carbs suck

[rodbolt17]

carbs actually work well.
however the passages are tiny and clog easily with varnish.
the thermal valve is easily tested yet rather expensive and is rarely the culprit.
typically if the carb is clean its either wrong starting procedure or an incorrectly set throttle plate.

[WET-BOX-MARINE]

i have had 3 this year that the thermo valve was not working
i wonder if the newer gas got past the o-ring or something

[99yam40]

i have had 3 this year that the thermo valve was not working
i wonder if the newer gas got past the o-ring or something

What they shortrd out or opened up electrically or they just would not move when 12 v was applied?

[WET-BOX-MARINE]

they would not fully close, causing a rich condition