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5 HP 2006 Mercury 4 stroke will not start

J

JanS48

New member
Greetings all
I just got an 06 Mercury 5 hp outboard that will not start. I've done the following:
Cleaned the carb, verified the carb is getting fresh fuel
Spark: Checked the spark plug - looks fine - when pulling it over with the plug removed it does spark but seems weak.
Valves: Checked the valve clearance and push-rod operation - seems fine.
Compression: 135
checked pulser coil - 200 ohms
checked coil under flywheel where it connects to CDI - is not open, is not connected to ground.
Even when shooting starting ether directly in the carb I don't get so much as a 'pop'
It appears the spark timing is way off - is there a way to check the timing or flywheel position relative to TDC on these motors?
Do these engines ever shear the flywheel pin?
Is there any common ignition component that fails? Coil ? CDI unit ?

Thanks in advance
Jan
 
More info...
I've checked the resistance of the coil under the flywheel -which is within spec.
I've pulled the flywheel and checked the key - everything was as it should be.
I swapped the coil with another one from another motor - not an exact replacement but I do get spark.
With the plug removed I spin the motor with a drill and checked with a timing light - marks are exactly where they should be [25` BTDC] per mark in svc manual.
Cranking the motor does not even yield a 'pop'.

Does anyone know if the ignition system has a way of telling when it's on the compression stroke vs between exhaust and intake stroke? Since it's a flywheel trigger I'm guessing the plug fires with every revolution - which is fine.

Everything checks out - this is not my first time to the dance... but there has to be something I'm missing. Do any Mercury mechanics read these threads? This has to be something that has been seen before.

Thanks
Jan
 
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