NO SPARK 1988 mercury 100HP outboard Sea Ray seville

[scotty8882003]

I used my boat all summer last year and go to put it in one last time before summer was out and it wouldn’t fire just turns over. I found that I have no power going to the plug wires when I crank it over. I replaced the rectifier and that didn’t help. Any other ideas on what it might be ? And does anyone have a wiring diagram for this motor?

 

[Chris1956]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

 

[scotty8882003]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

Could it also be a bad Mercury switch?

 

[racerone]

Disconnect mercury switch.---Test for spark.

 

[flyingscott]

Is that a 4 cylinder motor?

 

[racerone]

Yes that is a 4 cylinder motor and 2+2.

 

[Dave1027]

Also try disconnecting the black/yellow kill wire then test for spark. Edit - sorry Chris already mentioned that.

 

[scotty8882003]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

Do you know where I can get a service manual

 

[jimmbo]

Do you know where I can get a service manual

Ken Cook, or Evil-Bay

 

[scotty8882003]

Does any know what part number the stator is. I can’t seem to find the correct one online. Is it a 9amp one? Any help or links to the correct one would be great

 

[Chris1956]

Go to the crowleymarine site and punch in your serial number. It should give you an exact parts list.

 

[jimmbo]

Go to the crowleymarine site and punch in your serial number. It should give you an exact parts list.

Same goes for Marineengine.com and Mercury Marines Website

 

[scotty8882003]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

Now is it common for the stator to go in these motors?

 

[scotty8882003]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

I did an ohms reading and have nothing on the blue wires but have a reading in the red ones.. so I’m assuming the stator is shot

 

[scotty8882003]

Check out maxrules for a wiring diagram. Pick a diagram for a motor close in year and with the same number of cylinders. Anything after 1980 should be close.

That motor will have ADI ignition. That is the flywheel spins generating voltage in the stator. This voltage is fed to the switchbox, and when the trigger signal is received, a pulse of voltage is fed to one of the ign coils. So your issue is bad stator, bad switchbox, bad trigger, bad ign switch or bad wiring.

Usually the engine needs to spin 300RPM when cranking to generate spark. If unsure, remove spark plugs to make it spin faster.

Disconnect the black/yellow wire at the switchbox and see if spark returns. If so, ign killer wire is grounded somewhere, perhaps the ign keyswitch.

A service manual will have ohm tests for coils, stator, and possibly the trigger. CDI Electronics may have a test for the switchbox, but I would start with inspecting the wiring.

Well I replaced the stator/trigger and rectifier and took the key switch out of the equation and still have no spark. I am now only left with the switch box. Hopefully this works. If it doesn’t I am at a loss

 

[Chris1956]

If your rectifier is shorted to ground, it can hinder the spark. You might disconnect the yellow wires from the rectifier and insulate them. Repeat the spark test.

 

[scotty8882003]

If your rectifier is shorted to ground, it can hinder the spark. You might disconnect the yellow wires from the rectifier and insulate them. Repeat the spark test.

I forgot to add that as well. I did try that as well took the yellow wires that come from the stator to the rectifier abs still nothing