My Optimax has always from new seemed to crank for along time before it finally fires and then it runs great.
I have replaced all the fuel lines, filters, plugs, cleaned the VST and pulled the fuel rail and checked all the injectors for dirt, blow by and direct injector leak back. Everything checks out perfectly and all the seals and o rings look in great shape. I checked the fuel and air pressure with it running and air was 80 psi and fuel was 95 psi.
In my Mercury workshop manual it says:
”Compressor Note: To aid starting when the air rail pressure is low and before the compressor has time to build pressue, some direct injectors are held open by the PCM. This allows the compression from inside the cylinder to pressurize the air rail faster”
I believe this is the problem! If I stop the motor and then immediately restart, it fires right up, but if I wait a minute or so, it cranks forever.
It’s so bad that it destroyed the ring gear and starter motor dog and of course Mercury will only sell a complete flywheel a starter.
Does anyone have an idea how to get this “ cold start” functioning? I talked to a local service guy and frankly I knew more about the system than he did, but he does have access to the Mercury computer if it’s something in the PCM.
Any help would be greatly appreciated!
I have replaced all the fuel lines, filters, plugs, cleaned the VST and pulled the fuel rail and checked all the injectors for dirt, blow by and direct injector leak back. Everything checks out perfectly and all the seals and o rings look in great shape. I checked the fuel and air pressure with it running and air was 80 psi and fuel was 95 psi.
In my Mercury workshop manual it says:
”Compressor Note: To aid starting when the air rail pressure is low and before the compressor has time to build pressue, some direct injectors are held open by the PCM. This allows the compression from inside the cylinder to pressurize the air rail faster”
I believe this is the problem! If I stop the motor and then immediately restart, it fires right up, but if I wait a minute or so, it cranks forever.
It’s so bad that it destroyed the ring gear and starter motor dog and of course Mercury will only sell a complete flywheel a starter.
Does anyone have an idea how to get this “ cold start” functioning? I talked to a local service guy and frankly I knew more about the system than he did, but he does have access to the Mercury computer if it’s something in the PCM.
Any help would be greatly appreciated!
