Voltage to auto choke, 2009 buddy 125

Bill61 · Post by **Bill61** » Wed Jul 17, 2019 12:54 am

>Anyone know what the voltage should be at the orange 2 pin plug that goes to the carb auto choke? DC or AC?
>Are there aftermarket auto chokes available? Put 12V DC to the choke unit, no movement.
Resistance is 5 ohms.
>No start, run condition. If I cover intake side of carb with my hand, scoot will start. Does not continue running when I remove my hand. Hand gets wet with gas. Dies when increasing throttle.

babblefish · Post by **babblefish** » Wed Jul 17, 2019 3:10 am

If memory serves me right (those more knowledgeable feel free to correct me), the choke is powered by the alternator (stator) so is AC powered. The voltage should be anywhere between around 11 volts to 14, depending on engine RPM. It also defaults to being ON, meaning it's providing extra fuel to the engine when it is cold. When the engine is started, power from the alternator causes an element in the choke to warm up eventually closing off the extra fuel provided for cold running.
The symptoms you describe makes it sound like you may have an air leak somewhere between the carb and the engine. I would also check for a loose spark plug just in case. It also wouldn't hurt to check the intake valve clearance to make sure it isn't too loose thereby preventing the valve from opening enough to keep the engine running.

Stanza · Post by **Stanza** » Wed Jul 17, 2019 2:26 pm

Sounds like a plugged idle circuit. Your hand gets wet because it's sucking extra fuel through the main jet. I'm guessing it will keep coughing and stumble-running if you keep blipping the throttle at idle?

Bill61 · Post by **Bill61** » Thu Jul 18, 2019 10:53 pm

Update and thanks for the replies.
Spun motor with starter, not running, got 6V AC at the choke connector.
Took apart carb, cleaned with aerosol cleaner and compressed air.
Scoot starts. Eratic idle. Blip the throttle at idle, will not return to idle. Adjusted idle screw to no avail.
Road test, at WOT, has misfire. Pulled plug, correct PN. Very wet.

charlie55 · Post by **charlie55** » Fri Jul 19, 2019 1:31 am

A wet plug after running WOT indicates to me a possible problem with the float. Check the float height and the condition of the float needle and seat. Also, make sure the float hasn't sprung a leak.

Bill61 · Post by **Bill61** » Fri Jul 19, 2019 2:21 am

Update, thanks for replies!
Replaced spark plug.
Lubricated throttle linkage at carburetor with Krioil.
Added 5oz of Berryman B12 to 1 gallon in tank. Idled and blipped for 15 minutes. 2- 5 second WOT runs.

Result : returns to idle better, not perfect. WOT , stumble and misfire.

What are the options available for a new carb? Other than OEM @ $265?
No fuel pump? Seems odd. My 50cc Honda Metropolitan has a fuel pump.

scootERIK · Post by **scootERIK** » Fri Jul 19, 2019 4:45 am

Have you checked the diaphragm in the carb? You need to make sure it is full seated and that it doesn't have any holes in it. That would be the first thing I would check based on the problems you are describing.

Modern Buddy