Re: Merc 1976 model 1750 Boat motor bogs out when I try to throttle up under load?
Problem resolved,
I found only 4 cyl where firing not all 6 I could not tell when motor was running. I talked with a boat mechanic
He told me yes you can?t tell? You can be running on 4 cyl and the motor will pure like a kitten just like every thing is ok. From a coil test I did I found #2 and #5 cyl Where defiantly not working do to these coils where bad I checked the sec-coil {Sparkplug wire to engine ground} on cyl 2 & 5 was Open Load and aprox 1000 ohms on cyl 1,3,4 and 6 My repair manual says should be 800 to 1400 ohms I checked these coils and they where also had crack?s I replaced coils and 6 cyl still not firing. Replaced two switch boxes and now motor sound different and even stronger. Went to lake and tested all ok. My manual says if you want to test switch boxes you need to take them to dealer for this. I can tell you for sure these coils where bad and something happened to these switch boxes.