Coil wiring

[fredyacht]

4.3 mercruiser, 2000yr, thunderbolt ignition. No spark. new block and we are putting all the wiring back on. What wires attach to the coil. 12v to + terminal, what wire attaches to the - terminal. engine is out of the boat on a stand, we are cranking with 5 6 and 7 at the harness connector. Help. pictures would be great.

 

[achris]

Have a read of this... Everything you need to know (and more)...

How Mercruiser Thunderbolt ignition systems work.

Mercruiser Thunderbolt ignition systems. Mercruiser introduced the Thunderbolt IV onto their engines in 1982, alongside the introduction of the 1-R drives. The TB-IV system was used until the introduction of TB-V mid-way through 1996. Thunderbolt V was an improvement on an already exceptionally...

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[Bt Doctur]

Typically there are 2 purple on the + and 2 grey on the - . Again depends on what ign module your using