Base timing doesn't change grounding purple/white wire

[harcos]

Looking for help timing my engine. I have a 1996 Mercruiser 4.3 LX Gen+ with the thunderbolt ignition. Bought it with a split block and just finished installing a new engine. Have it running and got it up to temp and idling nicely. I grounded the purple/white wire to set the timing @ 10 deg and noticed that it makes no difference whether it is grounded or not. I also noticed it doesn't advance when I increase rpms.(purple wire not grounded then). Any suggestions that save me time diagnosing would be much appreciated.

 

[alldodge]

Module might have burned out

Try this for dumps and giggles just to make sure.
Engine OFF and connect jumper. Start motor and check timing to see if its at the same spot

 

[achris]

Make sure the Purple/white wire isn't grounded inside the harness (test with a multimeter to ground)...

Do you have knock sensors?

Chris....

 

[harcos]

No I don't have knock sensors. I had the engine off before grounding the jumper and checking the timing as per the procedure. I will check to see if the purple wire is grounded that is a good suggestion. I will also trace it as it seems more likely that it may have an open. Also want to add that I was wrong about the timing not advancing when I rev the engine, it does advance so the module should be OK. Thanks guys for the suggestions I will try them later today.

 

[harcos]

Purple wire is not shorted to ground nor is it open circuit (4k ohms). Sounds like it could be the module even though it does advance as it revs up. Not sure what else it would be. The tach doesn't work so that could be another module indicator as wiring all seems correct. Also and I don't know if this is connected but I think the warning beeper under the instrument panel is also tied into the ignition module from what I can see on the wiring diagram and it beeps continuously while it is running even though oil pressure and temp are OK. The beep isn't full volume, more like it's not fully off rather than signaling a fault if that makes sense. Oh the fun we have with new used equipment right. If anyone knows a way to test the module other than the old "replace with a known good one: I would appreciate it. Thanks

 

[76SeaRay]

With it at half volume on the warning sensor almost makes it sound like you have a bad ground somewhere in the system.

 

[alldodge]

Is the drive lube bottle full?
If it is, disconnect one of the wires to see if alarm stops

 

[harcos]

Is the drive lube bottle full?
If it is, disconnect one of the wires to see if alarm stops

the alarm get louder when it thinks the bottle is empty, good suggestion though thanks

 

[harcos]

With it at half volume on the warning sensor almost makes it sound like you have a bad ground somewhere in the system.

I am thinking the same which is why I suspect the module as it seems to be the control for the sensor. I will go over the wiring again though to be sure. Thanks you