2002 mercruiser 43litre no spark

"2002 mercruiser 4.3litre. The

"2002 mercruiser 4.3litre. There is no spark. Using the Mercury Service manual we went through the decision ladder -- no spark -- 12v into the ignition module -- zero volts out of ignition module -- solution, change ignition module. There have been four ignition modules installed, two brand new from Mercury and still no spark. At this point I don't think it is the module. Perhaps one of the inputs into the module? Any suggestions?"

"why did you put 4 modules on

"why did you put 4 modules on it? what sort of voltate does the manual call for out of the module, a square wave?"

Check your kill switch and you

Check your kill switch and your shift interrupt switch.
Rod

I know of two kill switches: T

I know of two kill switches: The first is the lanyard switch which should be closed for running and it checks out so. The second is the shift kill switch which should be open to run and it checks so as well.
The story behind four modules (at $450.00 each) is long and does not contribute needed information. The important thing is all checked out "bad" according to the Mercury Service Manual.
All showed 12 volts in and zero volts out. Somewhere in the inputs to that module is a sensor or switch or wire that is broken. Anyone had this problem?

"Robert

""The story

"Robert

""The story behind four modules (at $450.00 each) is long and does not contribute needed information. The important thing is all checked out "bad" according to the Mercury Service Manual.""

Hmmmmmmmmm !!

Sounds a bit sus to me, I would be looking for the problem that has destroyed the 4 modules.

Peter C"

"Robert:
Is there a ground wi

"Robert:
Is there a ground wire missing on the ignition module bracket?

Time to unwrap the engine wiring harness to look for melted insulation from overheated wires, chafed wire insulation, breaks, etc. Feel each wire along its length and tug on connectors and the wire. Wire insulation should be supple and not hard or stiff."