2004 Yam 150TXRC no spark, starboard side

[1oldoutboardtech]

No spark on starboard side?

I do not have jumpers to test the voltage while running. I unplugged the charge coils and pulser coil leads and did a cranking output and ohms test. Both where good. From my years of experience I know that if you have good input into the cdi unit and you have spark on 3 coils and no spark on 3 coils you are not going to get a reading on the leads from the cdi that are not firing. so therefore I have not actually taken a voltage reading from them. Is there a reason I should? Once again I am a Evinrude/Johnson tech and as I am finding out Yamaha ignition systems work a lot different. I have checked the grounds but I have not disconnected the kill wire which I think is what you ask. Not sure which wire that is but if that was a problem wouldn't I have no spark at all? Also as I have stated before this model does not have a shift assist switch.

[99yam40]

you wrote you checked peak voltages into the CDI, but did you check voltages out of it?

If you take the reading at the CDI you will eliminate wiring to the coils.
did you disconnect the kill wire at CDI also when testing?

Did you take th grounds loose, clean and re-tighten?

[1oldoutboardtech]

No spark on starboard side?

This boat is run in fresh water so everything is very clean but I still checked all the grounds I could find. All where tight and clean.

[boscoe99]

Just a wild thought but each cylinder head/cover, into which the spark plugs are screwed, is grounded to the block via a small jumper. I would check that jumper to ensure the connections at both ends are clean and tight.

No groundee no sparkee.

[1oldoutboardtech]

No spark on starboard side?

Yes I have lost spark on all 3 coils on the starboard side. I switched the leads from the cdi unit to the coils and got the other side to spark just to make sure all 3 coils where not bad. So am I understanding you right that there's nothing that you can point to and say ok if you have no spark on all 3 coils of the starboard side this would be the problem?

[rodbolt17]

unlike the 3.1L motors the 04 carbed 2.6L sparks 4 cylinders with two pulsers and a crank position sensor.
pulser one triggers spark for 1&4 the other pulser sparks 3&6.
the CDI uses the CPS to spark 2 &5.
the charge coils are high and low speeds but feed all 6 capacitors.
are you sure you lost spark on 1 bank or did you lose spark on 3 cylinders?

[1oldoutboardtech]

This problem started last year when a couple times it did not have full power at first but after a few minutes of running kicked in and ran fine. This summer from the first time I started it, it would not run at full throttle. I am a 35 year Evin/Johnson Tech but I am not up to date on 4 strokes and e-tech nor have much experience with Yam ignitions. I have done some reading up and what I came up with is the cdi unit. I got a used one and tried it with the same results. This unit could be bad too, I just thought it would be unlikely to have the same problem. The charge coils check within specs and so do the pulser coils although 1 side was .5 volts under what the book called for on cranking output I know meters can read different and I checked the output on a 115 yam with the same results. There is no shift assist switch on this model. It has been suggested to me that the wiring harness may have a short. I find this to be unlikely since I have power still on 1 side. Also if I disconnect the harness at the engine I also lose spark on the top port side. In my experience the way this started its a cdi unit but I want to make sure before spending that much money on a part. Please any suggestions welcome. It was suggested to me to look for rodbolt17 for help and I see you are on this site so hopefully you or someone can help. Thanks. Forgot to mention this is a carbureted and oil injected model.