I have a 1987 mariner 150, serial number 0B221329. I have had an issue for awhile that I posted about before. The issue was it would idle fine but has no power when under a load (accelerating). Carbs have been rebuilt, fuel pump is rebuilt with the updated black gasket, timing is correct, all cylinders are right around 110-115 psi (seems a out right for a motor this old). I had about given up but today decide to check through a few things again and when I checked for spark I have no spark in number 1 cylinder and cylinders 3 and 5 are weak, I can run the engine with very little change in RPM with 1,3, and 5 unhooked, I swapped coils from cylinder 1 to 3 and had no change, still no spark in 1. I've read through my manual for troubleshooting tips for the ignition system and all I can find is how to test the coils and the coils are working I swapped cylinders 1 and 2 and no change. I'm trying to find out if I need to replace the inner switch box, the stator, or the trigger or at least how to test these to see exactly where the problem is. This issue is getting expensive and after looking at cost of the ignition parts I would hate to keep throwing parts at this thing, the carbs and fuel pump needed done anyway as this boat sat for awhile before I got it but like I said I don't really want to spend any unnecessary money on more repairs. I'm leaning towards replacing the switch box since it appears to run all 3 cylinders but according to the wiring diagram both the stator and trigger appear to run the switch boxes. Hopefully I haven't gone overboard with the writing but just trying to get as much info as possible to someone who can help. Thanks for any help!
