Timing

[Nason]

What would cause the numbers to appear then disappear then re appear when you are trying to check the timing? Its not the timing light we checked it on 2 other motors. The motor runs good wot not sluggish at idle its a little rough. Could it be the coils, stator ,power pack,rectorfier ?
Thanks in advance for any help

[Bill Van Steenwyk]

What would cause the numbers to appear then disappear then re appear when you are trying to check the timing? Its not the timing light we checked it on 2 other motors. The motor runs good wot not sluggish at idle its a little rough. Could it be the coils, stator ,power pack,rectorfier ?
Thanks in advance for any help



It would be very helpful so as many folks that have knowledge regards setting and checking timing, if you could let us know what type and HP of motor you are working with, # of cylinders, and as much other information about this motor as possible.

Also you say that the "numbers are disappearing" when trying to check the timing.

Do you mean the timing marks on the flywheel are moving out of the range of the light when shining the light on them?

If that is the meaning of your post, perhaps you have a loose flywheel/sheared flywheel key, allowing it (flywheel)to slip on the taper of the crank, changing the timing while the engine is running. If this is the case, you might want to be careful until you determine if this is the problem, as if the flywheel slips to the advance side, you could burn or stick a piston.

Also if the timing on the motor is changed by the ECU based on RPM, perhaps the ECU is faulty. Either way be careful until you determine the problem as it is easy to stick or burn one if the timing changes uncontrolled.

Good Luck.

[Nason]

Thanks for the info. The motor is a 2005 40hp mercury 2 stroke 3 cyclinder. I tried 2 different fly wheels and both of the the lines/ number at idle you can see the numbers then they disapear then come back.You can see the numbers for 2-3 second then they disapear then 2-3 seconds later the numbers come back into the timing light.

[mercguy]

try the timing light plug wire clamp on a different cylinder (plug wire), just to see if the numbers stay consistant (even though not aligned with timing mark). If they do, then you could have a weak CDM (coil).....or even swap CDM's between a different cylinder....

[Bill Van Steenwyk]

Nason:

Mercguy is as good as it gets for this motor and this kind of problem. I am sure he can help you, as he has me with my V-6.

If you have already removed the flywheel twice, it should have been obvious if there was a problem with the flywheel key.

Good Luck

[Nason]

Thanks for the info, tomorrow I will give it a try.

[Nason]

Changed out the fly wheel key but it looked good, checked timing still not showing numbers. Accidently touched second CDM and Bam got lite up. Changed out the CDM and the numbers are back to normal. Now for another question. I pulled all 3 spark plugs out locked the motor in wot position and spun the motor it show 24 is that the correct timing ?

[HTarver]

Changed out the fly wheel key but it looked good, checked timing still not showing numbers. Accidently touched second CDM and Bam got lite up. Changed out the CDM and the numbers are back to normal. Now for another question. I pulled all 3 spark plugs out locked the motor in wot position and spun the motor it show 24 is that the correct timing ?

Yea, if you have never messed with changing the timing. Cuz stock timing on your motor is 24 degrees.

[dog74lover]

Changed out the fly wheel key but it looked good, checked timing still not showing numbers. Accidently touched second CDM and Bam got lite up. Changed out the CDM and the numbers are back to normal. Now for another question. I pulled all 3 spark plugs out locked the motor in wot position and spun the motor it show 24 is that the correct timing ?

Sounds about right to me.