1995 25hp yamaha has no spark.

[weekstown]

My 1995 yamaha 25 hp outboard lost all spark. It also is a pull start. Before I start buying parts I would like to know where and how to test for spark. Also how do I test the magneto for output and do magnetos generally go bad. Thank you.

[99yam40]

here is more than you wanted, but is good info on the systems

Print Out This Guide, The Use of Electronic Test Equipment for Outboard Motors.

and some more reading

Yamaha specs are around page 100 I think

CDI Electronics Practical Outboard Ignition Troubleshooting

If you are going to work on your motor yourself it is a very good idea to pick up a Yamaha service manual for you motor

[rodbolt17]

*** an easy question.
do magnetos go bad?? yep,they can.
however its not your issue as the 1995 Yamaha does NOT have a magneto.

see?? easy.

the 1995 Yamaha DOES have a charge coil AND a pulser coil(timer) to feed an AC voltage to a CAPACITOR discharge ign system.

a quick test,simply unplug the white wire at the CDI unit and retest for spark.

if still no spark you will now need a peak reading meter and the service manual.