115 H.P. Spark Question

[Charlie5653]

If I do a spark gap test with all 4 plugs out I get 7/16 spark

Then I put in the plugs and fire up the motor with the gap tester connected inline to one cylinder, and the spark is not consistent ? Maybe this is where my Idle miss is coming from but would it be coil or powerpack? On the water the motor runs 5100 rmp smooth as silk?

Thoughts?

 

[jakedaawg]

Might be best to better explain what issue you are trying to solve, what motor this is, etc...

an air gap tester online between a plug wire and an installed plug with motor running is not a test I have ever heard of anyone doing. Doubtful that any results could be considered valid...

idle misses can be various reasons.

simple as old coils and plugs leaking spark, running at night can sometimes see the spark arcing to ground.

some old v4 motors the plug wire could ground on the cowl latch....

need more info...

 

[Charlie5653]

A gentleman here asked for that test on a different thread (close to this one). I may have misunderstood what he was asking.

Thanks for your help, Charlie

 

[jakedaawg]

Post model number. Several 115's have been made.

cdielectronics.com has an excellent free trouble shooting step by step guide for any motor you may have. Your DVA and an ohmmeter will allow you to test it all in easy to understand language.

 

[Charlie5653]

Awesome Jake, Thank you very much!!

 

[Charlie5653]

Model 115ETL77S