1997 70 hp Evinrude no spark top cylinder

[Striperhunter]

I have a 1977 70hp Evinrude that is not getting spark on the top cylinder. I have changed the coils with new ones, changed the plugs, carbs were rebuilt and a link and sync done. Every once in awhile the top cylinder will fire and then it runs great, unfortunately this is not very frequently. Not sure where to look next and would appreciate any help I can get. Also compression checks good on all 3 cylinders 115, 110 and 115 :blue:

 

[Bosunsmate]

Re: 1997 70 hp Evinrude no spark top cylinder

You will need to check your timing base and stator.
Use the cdi ignition troubleshooter.
il look up the link

 

[Bosunsmate]

Re: 1997 70 hp Evinrude no spark top cylinder

Here it is.
Have a read through here.
Find your models description and test as per it says for spark not working on one cylinder.
I made a mistake above suspect faulty timing base and or powerpack
ISSUU - CDI Electronics Practical Outboard Ignition Troubleshooting by CDI Electronics

 

[Striperhunter]

Re: 1997 70 hp Evinrude no spark top cylinder

Thanks I appreciate the help