Procedure to test Stator on Mercury

[mthieme]

Testing the stator only requires an ohmmeter, you do not need to remove the flywheel. Disconnect the yellow leads to the rectifier. Disconnect stator leads from switchbox. Engine should be cold, resistance increases with temperature. Specifications are from a manual that only goes up to 1990.

1987 & up 100 & 115 HP
Between Blue and Blue/White stator leads 6000-7000 ohms
Between Red and Red/White stator leads 90-140 ohms

1987 & up 70-80-90 HP
Between Red and Blue stator leads 3600-4200 ohms
Between blue stator lead and powerhead ground 90-140 ohms

1980-1983 80 & 85 HP
1984-1986 75 HP
1984 & Up 60 HP
1980 & up 50 HP
1986 & up 45 HP
Between Blue and Blue/White stator leads 5700-8000 ohms
Between Red and Red/White stator leads 56-76 ohms
Between blue stator lead and powerhead ground No continuity
Between red stator lead and powerhead ground No continuity

1980-1983 70 HP
Between blue and red stator leads 5400-6200 ohms
Between red stator lead and powerhead ground 125-175 ohms

Manual does not note disconnecting leads to the switchbox on the following

1969-1979 80 HP
1973-1977 85 HP
1976-1978 50 HP
Between Blue and Blue/White stator leads 5700-8000 ohms
Between Red and Red/White stator leads 56-76 ohms
Between blue stator lead and powerhead ground No continuity
Between red stator lead and powerhead ground No continuit

1976-1979 65 HP & 70 HP
Between Blue and red stator wire 5400-6200 ohms
Between Red stator wire and powerhead ground 125-175 ohms

If you do not see your engine above, check here...
http://www.outboardignition.com/page39.asp

 

[merc850]

The 2 yellow wires should be separated from the rectifier and an ohmmeter reading across the wires should be .3 ohms more or less. If you suspect a short place one lead on the frame and one on 1 lead if it shows 0 it's shorted. Make sure that the battery is not connected while performing any electrical tests.

 

[gm280]

Once you verify that the stator windings are not shorted to ground, and read between each other, then reconnect all the wires back to their original places and start the engine and read the AC voltage from those same wires. if you read nothing....look for a new stator. But only after verifying that the rectifier isn't shorted as well. If you can read anything on the stator wire places on the AC side of the rectifier (with the stator wires removed) then you have a rectifier shorted...

 

[chrisparry]

Testing the stator only requires an ohmmeter, you do not need to remove the flywheel. Disconnect the yellow leads to the rectifier. Disconnect stator leads from switchbox. Engine should be cold, resistance increases with temperature. Specifications are from a manual that only goes up to 1990.

1987 & up 100 & 115 HP
Between Blue and Blue/White stator leads 6000-7000 ohms
Between Red and Red/White stator leads 90-140 ohms

1987 & up 70-80-90 HP
Between Red and Blue stator leads 3600-4200 ohms
Between blue stator lead and powerhead ground 90-140 ohms

1980-1983 80 & 85 HP
1984-1986 75 HP
1984 & Up 60 HP
1980 & up 50 HP
1986 & up 45 HP
Between Blue and Blue/White stator leads 5700-8000 ohms
Between Red and Red/White stator leads 56-76 ohms
Between blue stator lead and powerhead ground No continuity
Between red stator lead and powerhead ground No continuity

1980-1983 70 HP
Between blue and red stator leads 5400-6200 ohms
Between red stator lead and powerhead ground 125-175 ohms

Manual does not note disconnecting leads to the switchbox on the following

1969-1979 80 HP
1973-1977 85 HP
1976-1978 50 HP
Between Blue and Blue/White stator leads 5700-8000 ohms
Between Red and Red/White stator leads 56-76 ohms
Between blue stator lead and powerhead ground No continuity
Between red stator lead and powerhead ground No continuit

1976-1979 65 HP & 70 HP
Between Blue and red stator wire 5400-6200 ohms
Between Red stator wire and powerhead ground 125-175 ohms

If you do not see your engine above, check here...
http://www.outboardignition.com/page39.asp

is this test done when engine is off? I ask because my engine will crank (turn over quite healithy) but wont fire. Do you do these test whilst cranking or whilst engine is off?

 

[Chris1956]

Those are all ohm tests with the engine off, and the rectifier disconnected, and are for motors with ADI ignition. What are you working on?

Did you test spark with the black/yellow wire disconnected at the switchbox? That is the first test for ADI motors. If you have battery powered CDI, the test is different.

 

[chrisparry]

Those are all ohm tests with the engine off, and the rectifier disconnected, and are for motors with ADI ignition. What are you working on?

Did you test spark with the black/yellow wire disconnected at the switchbox? That is the first test for ADI motors. If you have battery powered CDI, the test is different.

I am working on Mercury 60 3 cyl 2 stroke. ADI...? sorry no idea what this is. No I didnt test with black/yellow wire disconnected, should I have? CDI has the 3 coil wires, blue, red, purple, brown, white, white/black, black, black/yellow all coming out of it, does that help. Thank you.

 

[Chris1956]

You might disconnect the black/yellow wire at the switchbox. That will remove the ign keyswitch and wiring from the test. If spark returns, troubleshoot the ign keyswitch and wiring.