Hello well to start off this motor has been sitting for quite some time before I got it, its a 1978 70 hp 3 cylinder 2 stroke motor, so when i got it the previous owner told me it needed a water pump because it will heat up after 15 min of running and will stall out and wouldn't run again until it cooled down, so i replaced the pump ( it was Fully in tact still) also replaced the coils , spark plugs and wires every thing seemed to be running fine she starts and idles great then going in reverse she bogs way down and when putting in a forward gear as soon and she engages she bogs out and dies, now i checked the spark and there's only spark on the top cylinder a good strong spark i tested it jumped 7/16" no problem but the bottom two absolutely nothing ? i was told its a bad power box how do i test that ? please any suggestions will help. I have not done the compression test but i'm doing that this afternoon just wanted some feed back if there was any other ideas that might cause this problem thanks in advance for your advice !
