I recently took my boat into a shop to have the gimbal bearing and drive coupler replaced. I got the boat back and it is not running as good as it was when I took it in.
The shop removed the carb and distributor when pulling the motor out.
When timing the motor at 8-10degrees before TDC the timing light starts to go crazy and it is firing faster or something. Then the rpm's start to rise to over 1200 rpm. I can get the boat running good but now I only get 4500rpm at best, before I could get almost 5000rpm. It is a non-magnum motor and has a carb. It is wired in the correct firing order,new cap,rotor,sensor wheel and igniton sensor. The shop worked on it forever and are stumpped and I worked on it myself for several days. They tell me that they tried another used ICM but I have not spoken to the actual person that did the work. I have done everything I know to do except replace the ICM and that is a little to expensive to just replace and hope it fixes it. I do know how to time these and did ground the purple/white wire to a good ground but it seems to me that the ICM is not going into base timing mode. It appears it is still advancing the timing anways.

I am looking at replacing the system with a Mallory YLU624AV and a Promaster E coil that I can get a great deal on, but would like to figure out what is wrong with my current set up as it has worked flawlessly until they pulled the motor out.
Any help would be greatly appreciated

If you cannot get the problem fixed here is the distributor I use. http://www.performancedistributors.com/marinedui.htm

Not to be sarcastic but have we pulled the dist. Made sure it's at TDC and tried reinstalling it? Engine was out, coould have gotten bumped and moved the crank a bit throwing it off a tooth.