1986 Mercury 50hp, no spark in full down position. Runs when tilted up.

perry_merc said:

ser# 08a996688

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Don't you mean
0a996688

We have been through this and convinced this is a bogus thread. If you do not change the engine harness this is just click bait. The only thing possible is the kill circuit tilt switch or harness.

check part 19 and 20 http://www.marineengine.com/parts/mercury_marine_parts/sn/0A996688/ 1045726/275_50 and all your earth straps and connections on rectifier/starter solenoid, also your main harness pins, when you tilt your engine watch the cables see what is moving. Make sure you have no lose cables. One last point is to check the old stator for scores on windings, does it have any?

My guess would be switch-box,you would need a DVA meter to test it.Or make an adapter for an ordinary multi meter.Youtube has lots of videos on how to make one.

Thank you UKMike. I will replace fuse and get this done today and post results.

I have a DVA tester on the way. Not much luck again today. I replaced the 20amp fuse, checked all continuity and earth wires including tracing them. I also removed the control box on my center console to make sure all was well. I did not see anything bad that stood out.

I know this is something simple but, just unable to figure it out. Frustrating. I do not see how it could be the switchbox, starts fine and has a strong spark while in up position. I am still going to test it. With the DVA tester I will be able to determine where I am losing spark in down position. That may help me trace it back and isolate.

I resolved my issue! Ready to get on the water for a full test. I replaced the switch box with a new CDI 114-5772 and have a nice blue spark when engine is in down position.
Thank you so much for all the help and responses, this forum is amazing and could not have resolved this issue without you.