bad charge coils?

[knot trying]

Ok so I got a service manual and started the diagnostics on my F9.9 - no spark on 1 cylinder.

Following a suggestion on the board, I replaced the ignition coil - wrong. Same cylinder - no spark (I have already swapped spark plugs and plug caps to eliminate them as suspects).

So the diags on the I measure the voltage on the CDI output (orange and black) to the ignition coil and it is very low. Should read at 1500rpm about 195 vac, reads around 7vac. So next I check the charge coil output. Should be 205vac, read 40vac.

The pulser coil read from 1-2 vac depending on speed, so it's probably ok.

So if I put this all together, a bad charge coil (didn't know they went out that easy) is not providing enough voltage to the cdi for the capacitor to fully charge and fire for both cylinders, thus only 1 cylinder fires. Very strange scenario, I would have thought that it would be quite random that each cylinder would fire sometimes, but it seems that 1 always fires and 2 never does.

Anyone else had any experience with this kind of failure?

Thanks.

[Ken]

knot,
I may be wrong, but I believe the signal from the CDI to the ignition coil should be a pulse, and not an AC voltage.
That 205 volts your service manual calls for is probably a "peak" reading and not a continuous ac voltage reading.
Some voltmeters will read "peak" voltage, or you could use an oscilloscope to see exactly what the CDI-to-coil signal looks like.
Good luck [img]smile.gif[/img] ,
Ken K

[boats.net]

Ken is right. The specs are listed for peak voltage. You can get a direct voltage adapter to fit some digital voltmeter's like Fluke meters that will read peak voltage.