1977 25hp Johnson no spark

[Ebulle]

I’m having issues finding out why I’m not getting a spark. The issue started when I hit bottom (think I spun a hub) prop would still spin in idle. Was making it back to the ramp in a idle speed when the motor died. Could not get it started back.Got it home and realized I was not getting spark changed spark plugs and have cleaned all grounds. Maybe CDI or coil packs? How do I test those? Any other suggestions?
1977 25hp Johnson seahorse

 

[racerone]

Model # of your motor?

 

[kbait]

No spark from both plug wires - shouldn’t be external drive coils (attached to cyl. head), as unlikely to both fail at once. That leaves charge coil and sensor coil under flywheel, CDI unit, or wiring as the culprit. Unplug the 2 wiring connectors and make sure pins are good/clean. Check wiring condition..especially where wires exit and flex coming from armature plate under flywheel. Google ‘CDI troubleshooting’ for Johnson/Evinrude to get normal resistance values to check your coils under flywheel (unplug big plug to test wires w/multimeter..follow instructions). if all the above is good, you have a bad CDI box.
Good luck!

 

[racerone]

New powerpack ( CD BOX ) fixes it 9 of 10 times.

 

[Ebulle]

Model # 25r77s
Ordered a manual it will be here this week. Also will start figuring out how to test each component to try and narrow it down. Just didn’t know what else I needed to test. Will get back with y’all. Thanks

 

[racerone]

Both coils did not fail at the same time.-----The stuff under the flywheel is very reliable.----Also very easy to test without removing the flywheel.-----That leaves the powerpack as the faulty part in most cases !

 

[Ebulle]

I put a new power pack on. Still no spark.

 

[jimmbo]

In your Initial Post, you mentioned that you had hit something. Have you checked the Flywheel-Crankshaft Key? If not yet, maybe the Key sheared, and that has caused many motor not to run well, or start

 

[racerone]

With a sheared key it would still have spark.----Test the charge coil and sensor coil.----Inspect pins / sockets at plug in connecters.