Right.. so I got cornered into fixing a 50cc 2 smoker and I thought I would share my findings into Autochokes in case anyone else comes into issues trying to figure it out.. seems to be a fine point missed on the scooter forums.
Scooter in question - 2012 Benelli Pepe 50cc. (Anther GY6 139QMB clone)
Issues - numerous - predominantly hard starting, stalling, dying on takeoff even when left idling, poor idle etc.
They had quite a bit of work done prior to tracing the fault.. probably needed doing anyway..
- Replaced roller weights and belt (originals stuffed)
- Replaced carb (original had been messed with, new jets etc) - all set per factory spec
- Replaced Autochoke
- Replaced starter motor
- Replaced vacuum petcock line
- Replaced battery (AGM)
The Autochoke has a nominal coil resistance of 330ohms when good. What I had failed to check was the upstream supply - I didn't have access to a wiring diagram and assumed that a new battery and good charging system would have been a sufficient check...
The autochoke has 12V supplied from a dedicated regulator mounted under the footwell at the front of the frame. The regulator gets its own dedicated AC supply from the alternator while the engine is running. The regulator then provides 12VDC to the autochoke element which closes the enrichment circuit once it has time to heat up and close the piston on the carb.
The regulator is a QJ 1E40QMB - or one of the many GY6 clone parts that exist out there. Did i mention it is a PITA to find on the bike???
It is also mounted in a location that can get drowned.. and they used a non water proof 4 pin connector.....
You can access the connector to the autochoke and measure for 12V with the engine running - if you get 0V you have a good chance the regulator is stuffed and the carb is running rich 100% of the time.. there are also other posts on how to check the autochokes themselves online.
Anyway, if this saves anyone some time I hope it helps.
