Hopefully some of you can help me out on this 1995 Johnson Ocean Runner V-4 90HP OIS2000 ignition engine. I'm helping a friend get it back into running order after sitting a good 4-5 years. Here's what's been done:
Model: J90SLEOC
Rebuilt all 4 carbs and sealed bowls to stop leakage from "BB's" that seem to be a common problem
All new gaskets on carbs and throttle plates
Linked and synched all carb linkages after installation
New spark plugs
New thermostats and seals
New water pump
Changed gear oil
Compression is good at 1-146, 2-139, 3-146, 4-131
Spark is good on all cylinders
After getting through all the work and prepping to run it, I'm finding that it will not hold idle for more than 10 seconds by itself unless you advance the plastic timing arm that peaks through the front of the engine under the protective cover on top. If you sit there and hold it about halfway it'll cooperate like a normal running engine in the summer but let go of it and it'll die off within a max of 10 seconds or so. I've tried to do all the synchronizing that I can do without having one of those OMC ignition analyzers that plugs into the optical sensor. Watched a youtube video today and saw how to replace the optical sensor but I'd rather understand the problem and diagnose everything before I start just replacing parts (that's the engineer in me!). I tried all the little and obvious things even adjusting the throttle cable out to see if that would help it but even with it all the way maxed it still behaves the same.
Is this something where I need the OMC ignition analyzer tool to diagnose and solve? I'm just at a loss at the moment and this project needs to be wrapped up ASAP and I'd rather have it be done and not be over my head all winter!
Any and all help or suggestions is greatly appreciated! Look forward to reading what people have to suggest.
Model: J90SLEOC
Rebuilt all 4 carbs and sealed bowls to stop leakage from "BB's" that seem to be a common problem
All new gaskets on carbs and throttle plates
Linked and synched all carb linkages after installation
New spark plugs
New thermostats and seals
New water pump
Changed gear oil
Compression is good at 1-146, 2-139, 3-146, 4-131
Spark is good on all cylinders
After getting through all the work and prepping to run it, I'm finding that it will not hold idle for more than 10 seconds by itself unless you advance the plastic timing arm that peaks through the front of the engine under the protective cover on top. If you sit there and hold it about halfway it'll cooperate like a normal running engine in the summer but let go of it and it'll die off within a max of 10 seconds or so. I've tried to do all the synchronizing that I can do without having one of those OMC ignition analyzers that plugs into the optical sensor. Watched a youtube video today and saw how to replace the optical sensor but I'd rather understand the problem and diagnose everything before I start just replacing parts (that's the engineer in me!). I tried all the little and obvious things even adjusting the throttle cable out to see if that would help it but even with it all the way maxed it still behaves the same.
Is this something where I need the OMC ignition analyzer tool to diagnose and solve? I'm just at a loss at the moment and this project needs to be wrapped up ASAP and I'd rather have it be done and not be over my head all winter!
Any and all help or suggestions is greatly appreciated! Look forward to reading what people have to suggest.