1992 Mercruiser thunderbolt 4

[Mercman2008]

troubleshooting no spark on 92 thunderbolt 4 ignition system. I was wondering with the key on there should not be power to both the positive and negative side of the coil right? Mine has power on both sides with the key on was wondering if that was normal and if not what could cause that!!! Thanks

 

[Bondo]

troubleshooting no spark on 92 thunderbolt 4 ignition system. I was wondering with the key on there should not be power to both the positive and negative side of the coil right? Mine has power on both sides with the key on was wondering if that was normal and if not what could cause that!!! Thanks

Ayuh,.... Welcome Aboard,..... The coil passes power, til the ignition grounds it, causin' it to fire off,.....

There's a diagnostic tree in the Manual, links to which you'll find in Don'S Adults Only section at the top of this forum,...

 

[Mercman2008]

thank you!!

 

[alldodge]

Page 3 has the troubleshooting guide
http://www.boatfix.com/merc/bullet/83/83_24.pdf