9.9 carburetor fuel enrichment wax disk

[hankstein]

I cannot find any explanation of how the fuel enrichment "starter set" operates. Some carbs have no electrical connection but use the wax disk others like my 2002 have the electrical connections. I've searched for the definitive explanation of how the enrichment device works and have found nothing. Is there anyone out there that KNOWS how the device works... Thanks.. 2002 T9.9EXHA

 

[boscoe]

I cannot find any explanation of how the fuel enrichment "starter set" operates. Some carbs have no electrical connection but use the wax disk others like my 2002 have the electrical connections. I've searched for the definitive explanation of how the enrichment device works and have found nothing. Is there anyone out there that KNOWS how the device works... Thanks.. 2002 T9.9EXHA

Carbs with no electrical connections generally use a mechanical choke plate.

The starter set you refer to is generally known by Yamaha as Primestart. Automatic fuel enrichment. When the motor is cold the wax inside the Primestart is cold. The Primestart needle is retracted. Allows more fuel to flow. Once the motor is started the motor feeds electrical current to the Primestart device. The wax inside heats up and extends the needle. As the needle extends less additional fuel is allowed to flow. Once the motor is warmed up the needle will be fully extended and not allow any more additional fuel to flow.