We need to check the timing on my buddys 2000 merc 454 MPI motor, is there any hoses or connectors that need to be disconnected ETC to check the base timing on it? also what is is supposed to be set at and at what RPM. he doesnt have the service manual for the motor and we need to pull the distributor out of it to change the pickup coil under the rotor so we need to see what it set at right now so we can get it back right when its back together.

thanks!

This is how you put the system into base timing mode. There is a diagnostic connector close to the ECU on the port side of the engine. You need to remove the plug end and jump a and b pins, bring rpms to 1500-1800, otherwise it jumps all over, then set the time with the timing light. Merc makes a tool that you can plug in for $10-15, 805747A2
I'm not sure exactly what the timng is on that year, but it should around 6-8 advanced. Someone will probably post what it needs to be at.

Follow the procedure above and set to 8*. If you don't have the timing jumper tool or a RInda scan tool (or similar), just jump out the A and B terminals with a small paperclip. I have both and I still end up using the paperclip.Bend the paperclip into a U shape and put it in once the engine is running. Then bring the rpms up to around 1800 or so and set it to 8*.
Eddie

thanks guys that worked perfect! it checked out at about 7 degrees when we checked it, we put it back around 7 to 8 degrees when we dropped the distributor back in it and it seems to fire up nicely now, hopefully the issue is solved now