View Full Version : 1996 120 HP Merc Force OBoard

04-06-2009, 06:40 PM
"First question. What type ignition system do I have?
Second question, Can the yellows be interchanged?.
Voltage Regulator (VR)
Gray to wire harness 13V
Yellow to Stator 13V
Yellow to Stator 13V
Red to Starter Solenoid
Yellow to VR
Yellow to VR
White/Green to Coil connector wire D 8.5 v
Green/White to Coil connector wire D 8.5 v
Black to Ground
Purple to Coil # 1 connector wire c .26v
White to Coil # 2 connector wire c .26v
Brown to Coil # 3 connector wire c .26v
Blue to Coil # 4 connector wire c .26v
I disconnected wire harness to motor and turned motor over via jump start solenoid. Third question, why no spark to any plug? All Zero spark.
Thanks for and assistance.

04-08-2009, 12:22 PM
"Brad, that model has Merc's CDM ignition system. They produced that for a few years (on V6 and a 3 cylinder model), didn't really like the results and gave up on it. But it is still 100 times better than the Prestolite ignition found on most Force models.

Yes, the yellow's can be interchanged - they are carrying AC which the voltage regulator will rectify to DC for the system to run on and it don't care which side feeds what on the input side of things.

Since this model has 4 individual CDM's, one for each of the cylinders, it is unlikely that all 4 died at the same time (or alternately all 4 wires or all 4 plugs).

If the trigger goes, it "usually" only takes down 1 or 2 cylinders at a time.

The CDM's also have blocking diodes so they don't release power on to another one, but again, that usually doesn't result in no spark anywhere if one of them goes.

So with no spark anywhere, I would suspect a bad stator..."

04-11-2009, 08:33 AM
Thank you for the information. I will order a stator.

04-11-2009, 11:24 AM
My stator is black 398-9873A22
I see two stators listed for this A22 part number on 9 amp and the other 16 amp. Can you help me with getting to correct one?
Are the red ones better than the black ones?

04-11-2009, 03:38 PM
"The red ones are considered a "retro-fit" for some Merc models that originally had a black stator that is now discontinued.

The red stators however, are not simply a "plug and play" replacement.

Your model Force, came with one or the other, depending what Merc had on the shelf when they were moving along the production line.

The early black and red stators both produced 9 amps. The later model stators produced 16 amps and can be used to replace the earlier 9 amp models - so you do have some choices.

However, if you go with anything other than the original black stator, 9 amp, you will need the "kit" to make it work with your motor."

04-11-2009, 03:57 PM
"OK cool. I was not sure if the power out put would of 16 amps would start frying things. So how does one know all the information.
Thanks again I will order the 16 amp I guess, MMMMMM more power. I checked all the CDM and all checks where good. So hopefully I will be
out next week. If you need to know any thing about the BQM-74 let me know.

04-11-2009, 04:15 PM
"No the black ones are interchangeable 9 or 16 volt - they were used on 2, 3 and 4 cylinder Mercs.

They normally put the 9's on smaller horsepowers and the 16's on the larger ones with electric start, power trim/tilt etc.

The red stators put out a different voltage that, without either changing the switchbox or installing an adapter, would fry the ignition system on motors designed to use the black stators..."

04-11-2009, 04:27 PM
OK so I need a black 9 amp to replace my stator.

04-11-2009, 10:12 PM
"I would go with the 9 amp black unless you are using the motor to charge a couple battery banks, otherwise the original is more than enough to keep your starting battery up to strength and run the fish finder/nav lights..."