I have a 22' bay boat with a 2002 mercury 150 saltwater series engine. Boat and engine have about 300 hours on them. The boat is a friend's that I am looking to buy. It sat up for a year and the first time I took at out it would barely turn up 4000 rpm. I took it to a shop and had the carbs rebuilt. The tech felt confident that was the problem.
I took the boat out today and the max it will turn up is 4500-4600 rpm. It is slightly missing at that rpm. Compression is even at 125 per hole. Boat runs like a champ under 4000 rpm. 19 Pitch prop.
I even tried choking it(pressing in the key) at WOT to provide some fuel enrichment....nothing changed. Where should I look next? Do a test on each coil? Can I just use a simple spark plug gap type tester? Does someone have primary and secondary impedance specs on the coils?
The fuel is at least a year old but was stored with stabil. Have no idea when the last time the water separator filter was changed. Could old fuel do this?
I took the boat out today and the max it will turn up is 4500-4600 rpm. It is slightly missing at that rpm. Compression is even at 125 per hole. Boat runs like a champ under 4000 rpm. 19 Pitch prop.
I even tried choking it(pressing in the key) at WOT to provide some fuel enrichment....nothing changed. Where should I look next? Do a test on each coil? Can I just use a simple spark plug gap type tester? Does someone have primary and secondary impedance specs on the coils?
The fuel is at least a year old but was stored with stabil. Have no idea when the last time the water separator filter was changed. Could old fuel do this?