1997 Yamaha 90hp C.D.I Diagnoses 90hpExcept

[Yama-Out90]

I have a 1997 Yamaha 90hp. All the 97 Yamaha 90hp models use the same C.D.I. except the C90, which is 6H0-85540-03-00. I am having a cold weather problem with the middle cylinder. The CDI is not firing to the middle cylinder until the engine or outside air temp get warm, then it runs perfect. Guess it is time for new CDI or head out when it is always warm outside.

 

[robert graham]

Have you checked the spark plugs, wires and coils to be sure it's not the problem?.....

 

[boscoe99]

The CDI is about the least likeliest part to fail.

Why not remove the CDI and warm it up inside to ambient room temperature or a bit warmer if you keep your house frosty. Then install it on the motor and see if the motor now starts when the motor is cold. If it is the CDI that has failed then so be it. Install a replacement. I would just be hesitant to buy and replace the CDI just because it is suspect. More than likely you will have a spare surplus CDI.

 

[Yama-Out90]

Yes the problem never moves with plugs or coil pack, or work with plug or coil pack from a functioning cylinder. Not coming out of CDI to coil pack. Warms up, it comes out. Will try the warm up in house while cold outside, then reinstall and test. Thank you for responses.