Thread: 25 hp yamaha 4 stroke hard starting

Check your choke for proper operation.

Has no choke ,uses something called prime start.

Originally Posted by ichabod

Has no choke ,uses something called prime start.

That is your choke. When you push the key in gas will squirt into the carb in pulses. When starting the first time that day hold the key in while starting. When it fires, stop choking. Also when the key is on, push it in and you should hear the primer solenoid click if it is working. At least this is the way it works on Mercs. Hope this helps.

On Mercury models, it's called an enrichener. Does not reduce air coming in like a choke, just shoots a little extra gas in when you hold the key in. Similar in theory, however.
Has the cold start bugaboo just recently started? Is the bulb squeezed until very hard? Any chance your bulb may need replaced?

Yamaha uses a completely different enrichener system than Mercury. And it's automatic. If it's having issues, have the carb cleaned and replace the spark plugs. That should put you back to normal operation.