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1970 Mercury Thunderbolt Help

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Bassin212

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Hi everyone, New to the site and don't know too much about outboards but hoping some of you brainiacs can help me out. I have a 1970 2 stroke Mercury Thunderbolt 50 HP. Got it worked on last year(Spark plugs, filters, and carbs) it ran fine but the mistake I made was not winterizing it. Last night I went to take on the task of getting it running again and I turned the key and I got about 6 good turns of the key with the boat trying to turn over until suddenly on the 7th turn of the key it was just one click and no turn over. I thought maybe it was the battery (which is brand new) charged it all last night, fish finder works and says I'm getting about 12-13 volts but this morning still just click and dead no turn over. Finder still reads about 13 volts so I don't think its the battery, and all new spark plugs last August any suggestions or help would be great! Good luck on the early spring this season everyone!
 
Leave the good battery hooked up as it is.-------------Now take one booster cable and go direct from battery positive to post on starter.-----What happens ?
 
I tested the voltage of the starter and the battery, everything is full voltage but I think I may have found the problem. I am going to try and take a picture of it and post it on here.
 
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So I'm thinking this is the problem. This is the picture of my starter it spins freely when I spin it with my hands however it won't move up at all so I'm assuming it froze? Because the starter should be spinning the big red gear at the top? Any thoughts or suggestions?
 
UPDATE: I took Racerone's advice and took jumper cables from my battery and connected them to my starter. Turned the key I get sparks but nothing spins and the starter doesn't spin or jump up.
 
Then I screwed that one up! But I did take the starter apart saw that one of the wires was fried up, rewired it and put the starter back together and on the outboard, Turned the key and the starter spun a little and shot up but then wasn't moving much. so I turned the key off and then when I went to turn it again same thing happened as before. no turn over no starter engaged just a click with nothing followed.
 
I am so thankful for this forum, I am also having a similar problem that you have already been over,I see that you were having a problem with a spark plug wire,well I have a wire in a similar condition the end it off with and I was wondering also just like you if it was just like a car pull the peace out clean the hole and get a new wire,the wire was hard coming out and I was worried that since it was such a confined engine compartment that it was somehow squeeze down to help prevent spark and Accidental Fire,I guess I've been lucky because I just got this boat 2 years ago and it's been pretty well maintenance free and a good runner so I thank you for the information and I will be getting busy.
 
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Good evening! Could someone help me? I need the circuit and its component details for the nit encapsulated within stator number 336-3996A4.
Mercury Motor, serial number 02814730, year 1970.
Thanks.
 
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