Jayzimmerman3
Recruit
- Joined
- Jun 7, 2020
- Messages
- 2
Hi all,
I am at wits end with this motor, and hoping for someone much wiser than I to provide some input. I bought a boat project, which had a blown 1996 120hp force outboard on it. I bought a 1990 hp motor which wasn't running but had really good compression (140-150 every cylinder). I took the CDM? (I believe that's what it is called on the 96) modules, rectifier from the blown motor and installed them on the 1990 (using wiring diagrams to make sure everything lined up correctly). Must to my happiness, it roared to life on the engine stand and seemed to be happy running on muffs
I later installed it on the boat and took it to lake and found that it wouldn't get over 2k rpm, bogged down heavy and was just lacking power. Did some hunting and found that I accidentally snipped some wires and it was only running on 2 cylinders. Fixed that, and new plugs and carb gaskets, and cleaned and reset carb air fuel mix screws.
Took it to the lake again, and was running pretty well, but wouldn't get over 3500 rpm. Still was enough for some fun with fam. Took it out next week, and started bogging down after a few seconds. I took it apart and had wet, milky plugs. I found that water was leaking into top 2 cylinders and killing those cylinders. Took the exhaust plate off and replaced gaskets, also changed head gasket (confirmed it was blown on #1 cylinder).
Did all this, and took it out yesterday and still couldn't get it over 3700 rpm, and it would big down again and drop in rpms to about 2700, although not as fast as previous times. I am running out of ideas and losing hope in this whole project thing. I don't want to keep throwing money at this. Any next steps or ideas? Did I miss something major? Do I need to mess with the timing after changing the CDI modules out for the newer CDM?
Many thanks!!!!!
I am at wits end with this motor, and hoping for someone much wiser than I to provide some input. I bought a boat project, which had a blown 1996 120hp force outboard on it. I bought a 1990 hp motor which wasn't running but had really good compression (140-150 every cylinder). I took the CDM? (I believe that's what it is called on the 96) modules, rectifier from the blown motor and installed them on the 1990 (using wiring diagrams to make sure everything lined up correctly). Must to my happiness, it roared to life on the engine stand and seemed to be happy running on muffs
I later installed it on the boat and took it to lake and found that it wouldn't get over 2k rpm, bogged down heavy and was just lacking power. Did some hunting and found that I accidentally snipped some wires and it was only running on 2 cylinders. Fixed that, and new plugs and carb gaskets, and cleaned and reset carb air fuel mix screws.
Took it to the lake again, and was running pretty well, but wouldn't get over 3500 rpm. Still was enough for some fun with fam. Took it out next week, and started bogging down after a few seconds. I took it apart and had wet, milky plugs. I found that water was leaking into top 2 cylinders and killing those cylinders. Took the exhaust plate off and replaced gaskets, also changed head gasket (confirmed it was blown on #1 cylinder).
Did all this, and took it out yesterday and still couldn't get it over 3700 rpm, and it would big down again and drop in rpms to about 2700, although not as fast as previous times. I am running out of ideas and losing hope in this whole project thing. I don't want to keep throwing money at this. Any next steps or ideas? Did I miss something major? Do I need to mess with the timing after changing the CDI modules out for the newer CDM?
Many thanks!!!!!