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1976 Mercury 65hp 650 thunderbolt ingnition problems please help

Spongerssuck206

New member
I have a 1976 650 thunderbolt 3cylinder, and I am having trouble getting all my cylinders to fire. I was out running the motor one day and all of a sudden i lost half my power. took it home my and my number 2 cylinder wasnt firing. All my coils are good i checked that. ( i have a second motor that i am using for parts). I took the switch box off of the other motor and switched them out.... still the same cylinder didnt fire. I pulled my flywheel off and checked the stator and the trigger assy. I switched the trigger system out and now i have #1 cylinder only firing, 2 and 3 wont fire.

Questions is what would be the problem causing this could it be my stator or my trigger assy. I re-placed the wires on the trigger assy i switched. I just dont want to buy the wrong part and still have the same problem. Im trying to get this thing going before summer
 
Sometimes a stator or trigger will give good readings cold,then when the motor warms up and everything expands it cuts out.Test when cold,run motor until operating temp,if not possible,then heat with a hairdryer and test again and see if there is a difference.There will be a small difference,what you are looking for is big differences.
 
Well what would most likely be causing the cylinders not to fire the trigger assy or the stator. i figured if the stator was bad i would be getting no spark at all on all of them.
 
The stator is the alternator and basically charges the battery.The trigger on the other hand sends the signal to the coil to fire.
 
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You can test the trigger coil with a meter; if there's continuity, it's wroking. It's just a simple coil.

Jeff
 
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