Mercury Mark 7 Top Cylinder

Captain Mercury

Captain Mercury

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Does anyone know which coil....in this two coil two cylinder system would be assigned to the top cyl. ?? :facepalm: The engine is a 1954 Mercury Mark 7 7.5 hp serial number 759821. I got the engine and the ignition system was in pieces and now I'm trying to put it all back together and need to know how to determine which coil/plug wire goes to the top cyl. etc. I have new coils, new breakers, new condensers and plug wires.
Any help would be greatly appreciated...I have looked at an exploded view of the ignition system but can't determine left/right or front/back...Help ! :confused:
 
merc850

merc850

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Re: Mercury Mark 7 Top Cylinder

Put a pencil in the top cylinder and rotate the flywheel clockwise until the piston moves up to TDC, the coil that sparks near this position is the Nr. 1 cylinder one.
 
Captain Mercury

Captain Mercury

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Re: Mercury Mark 7 Top Cylinder

"merc850"......If I apply this method, will the points that are closed or the ones that are open be the ones that are sending the current to the #1 plug since there are two points breakers.? :confused:
 
merc850

merc850

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Re: Mercury Mark 7 Top Cylinder

The points that are opening, you'll be able to see the hi point of the cam touching the point arm.
 
Chinewalker

Chinewalker

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Re: Mercury Mark 7 Top Cylinder

Pretty sure it holds true that the forward coil fires the top cylinder...
 
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