I have a 1990 Thompson 26" fisherman with a 5.7 liter mercruiser with an alpha outdrive. Got towed off of Lake Ontario yesterday when engine died. Engine had no spark at plugs or at coil. Per service manual check for 12v at + side of coil, that was good, then checked for 12V at the distributor, also had 12V there. Then checked for spark from coil lead to ground - no spark. Tried known good coil - still no spark. Manual says that if all the above are true it is the ignition amplifier mounted on the exhaust manifold. As this is like a $300.00 part I want to be very sure it is indeed bad. Is there any way to bench test amplifier with a meter to confirm it is bad? If not could a Mercruiser dealer test it for me? Any help would be greatly appreciated. Thanks!
