I have a new to me 98' Mercury 150 XR6. I bought it knowing it had good compression (125-130), but was not running right. This came on a 98' Nitro Savage 884. When I went to check out the boat/motor I could tell right away that the carbs were flooding the engine. Took it out on the lake and it was bogging down bad enought to not get on plane or get past 2k rpm. Figured it was going to be an easy carb rebuild and good to go. Fully dismantled the carbs, soaked them in Berryman carb cleaner for a day or so, sprayed them out with some aerosol carb cleaner and shop air. Reset the floats (which were way off when I took them apart) and reassembled. Synchronized everything whe it was reinstalled. Rebuilt the fuel pump while I was at it and replaced plugs/wires. Carbs seem happiest at 2 turns out. The engine will now accelerate, and get on plane but won't go above about 4200 rpm at about 40 mph. Similar boat/engine/prop owners are getting 5200 rpm and 58-62 mph. I can tell right at about 3200-3300 rpm it starts to break up a little right as it's getting on plane. I can trim up a little and get it past that point but again it won't go past about 4200 rpm WOT. It feels like an ignition misfire based on my automotive background. I can feel, for a brief second intermittently, where the engine fires on all cylinders normally. A noticeable brief increase in power, but goes away just as quickly.
I have ohm tested the stator and it at least ohm tested fine on both low and high speed sides. I have a DVA on the way. I ohm tested the Trigger as well, and the normal spec for it 1100-1400 ohms on each lead set. Two of them are testing right at 1250 ohms and one is testing at 800 ohms. Talking to some other folks they don't think that a trigger testing 800 ohms would necessarily be the issue? Any opinions on that? I was immediately just going to replace the trigger and the switch boxes but a lot of people are telling me 800 ohms (even though out of spec) isn't something to worry about and to just replace the switchboxes? Sucks that the only way to fully test is to put the boat in the water and sometimes its a week or two between opportunities. I did ohm test the ignition coils and all tested fine. At idle the engine has a strong, blue spark while running on a water hose. I know things can change under load and at a higher rpm/throttle input but maybe that gives y'all more info of a clue as well.
I have ohm tested the stator and it at least ohm tested fine on both low and high speed sides. I have a DVA on the way. I ohm tested the Trigger as well, and the normal spec for it 1100-1400 ohms on each lead set. Two of them are testing right at 1250 ohms and one is testing at 800 ohms. Talking to some other folks they don't think that a trigger testing 800 ohms would necessarily be the issue? Any opinions on that? I was immediately just going to replace the trigger and the switch boxes but a lot of people are telling me 800 ohms (even though out of spec) isn't something to worry about and to just replace the switchboxes? Sucks that the only way to fully test is to put the boat in the water and sometimes its a week or two between opportunities. I did ohm test the ignition coils and all tested fine. At idle the engine has a strong, blue spark while running on a water hose. I know things can change under load and at a higher rpm/throttle input but maybe that gives y'all more info of a clue as well.
