Replaced engine now no spark

I have a 1995 mercruiser carb 5.7 alpha one gen 2 combo with the thunderbolt 5 ignition original engine serial number 0F423587. system, that I recently replaced with a vortec reman unit because of a gutter that was created between cylinders 3-5, Before I realized the actual issue with this boat I had done the usual tune up, cap, rotor, plugs, and wires the boat would still start up and idle.

My current issue I'm having with this boat is, I have it all back together and I read the first thing you need to do is to set it into base timing. So I've grounded out the purple and white wire, and moved on to setting up the base timing only I have no spark. So I'm not getting anywhere, I start basic trouble shooting. The boats cranking, the electronics all seem to work, the trim is working. I have no voltage at the coil, so I move up front to the key switch, the red wire coming in has power it's flowing through properly I get over to the purple wire going out off the lanyard safety switch I disconnect it put my red probe on the switch outbound side and my black probe on the purple wire going back towards the engine I have battery voltage and at this point I'm lost and not sure where to check next. The main harness plugs looks to be in great shape I see no issues but still I'm losing power somewhere and getting 0 volts. With the fact that I can I touch the lanyard switch and the purple wire going back and get a voltage reading it is grounding out somewhere right ? My understanding is that the purple wire goes to the coil first and then the exciter on the alternator.

One other thing I have tried, was to disconnect the momentary killswitch and still had no spark.

With an old-school analog ignition system, I would jumper from the battery to the positive terminal of the coil, with a wire with alligator clips on each end. That should get spark, then work backwards until you isolate the break. Not sure if you can do that with your more modern system.

Candy Gramformongo said:

With an old-school analog ignition system, I would jumper from the battery to the positive terminal of the coil, with a wire with alligator clips on each end. That should get spark, then work backwards until you isolate the break. Not sure if you can do that with your more modern system.

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I'm pretty sure you can, if I understand the way the circuit works, the negative side of the ignition coil feeds then ICM. I did some more testing last, night and the way im reading the purple powers the coil, exciter, and the carb choke need to double check that last one but I did a multi meter test on the carb choke and was getting .81 volts so the voltage is trying to come through just losing is somewhere