yamaha f100

[5kjeff]

can some one tell me what the enrichment valve does

jeff

 

[Inducted]

Re: yamaha f100

If it is the manual style with the lever most likely it is for an emergency start. It will put some fuel directly into the intake. If the weather was real cold or your choke system wasn't working.

 

[yamatech43]

Re: yamaha f100

There is no choke system, the enrichment valve replaced it.....instead of restricting air to make mixture rich(wet), it adds extra gas to same amount of air....your key switch should activate it if pushed in while turning key to start....just push in key and hold while turning....engine will start easily this way.

 

[99yam40]

Re: yamaha f100

If you are speaking of the prime start assembly, unless the 4 strokes are different from the 2 stroke system it does not need operator to energize anything.
It is active at all times. When cold it allows enriched fuel to the cylinders and as the motor runs it feeds electrical power to a heater unit from the charging system, this heats up a wax pellet inside the enrichment valve that expands and pushes the valve closed , thus turning it off the extra fuel. At least that is how the one on my C40 2 stroke works