Hard start when cold

[craneman]

My fishing partner has a 1998 40MJH 40hp jet, when we try to start the motor when cold you have to crank it up to 20 times,it has done this since new. I don't think Yamaha had this procedure in mind. There dosen't seem to be a choke that I can find. Have read post of other people haveing the same problem,but no real definitive answeres. Once started and warmed up runs great, so I'm thinking fuel.
Thanks Moe

[99yam40]

What make you think it is a 98?
You did not post the whole model #.
Is it a 40 MJHW?

No choke means prime start model, so you need to make sure that is functioning properly and you have the red switch in the normal position.

A Yamaha service manual for that motor would help you out a lot

[craneman]

What make you think it is a 98?
You did not post the whole model #.
Is it a 40 MJHW?

No choke means prime start model, so you need to make sure that is functioning properly and you have the red switch in the normal position.

A Yamaha service manual for that motor would help you out a lot

From information given to me, will check into it further

[craneman]

Model number 40MJHY, where is the red switch you refer to to be in the normal pos.?

[99yam40]

Y is a 2000 model

red lever on #29 cover, should have sticker on silencer showing positions
2000 40MJHY Yamaha Outboard CARBURETOR Diagram and Parts

[craneman]

Can you tell me what that switch does. The manual says for use on emergency cold start. open then start the motor then close it.
thanks Moe

[99yam40]

You only use it if there is a problem (emergency) to get it started.
Should be kept in the full counterclockwise position(normal) if motor( carb)is functioning properly

[craneman]

Seeing the MJHY is manual start and no battery to activate the primer valve, how does the carbs get primed?
Moe

[99yam40]

You squeeze the primer bulb to prime the carbs(pump fuel into the bowls)

The prime start system is activated when motor cools off, as the motor runs if feeds voltage to the heater unit that closes of the needle as motor heats up

[craneman]

10-4 that's what I needed to know. This may have fixed the problem.
Thanks Moe