No Spark on #6

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Skeeter54

Seaman
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May 28, 2015
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Evening gents. After a long battle with my no spark issue I finally got it to spark and run! Now my only problem now is #6 is not. I do have to manually turn the throttle on the engine while a friend turns the key which after a few turns fires right up. Now the reason I mention this is I read somewhere that the lowest cylinder #6 would be the one to draw pressure for the fuel pump which is why I'm thinking this problem is tied together. Thoughts? And how do I fix the #6 issue
 
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Chris1956

Supreme Mariner
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Mar 25, 2004
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28,074
OK, does cylinder not have spark or does it not run, when the engine runs? Different reasons for each.

Do you not have a cold start lever or throttle only button on your controls?
 
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Skeeter54

Seaman
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May 28, 2015
Messages
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No spark and when it's running no spark. Throttle only on the controls but it seemed like when I did throttle only it barely moved the throttle on the engine so we manually throttled up for it to start. Also, when it runs it sounds like it's sputtering like one cylinder is not firing. Not sure about it running while the engine is on
 
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Chris1956

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Normally, a "throttle only" button will allow nearly full throttle in neutral. The Merc cold start lever only advances the throttle a small amount, but will give 1500 RPMs at least.

I still do not understand if you have spark in cylinder 6 when cranking or not. A timing light on that plug wire while cranking, will tell the tale.
 
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Chris1956

Supreme Mariner
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OK, No spark on #6 while cranking. Check the ignition coil for #6. Then check the CDIElectronics website for the troubleshooting procedure for stator and switchbox.
 
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Skeeter54

Seaman
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May 28, 2015
Messages
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Ignition cool has no spark. Stator and trigger are good. Sounds like another bad pack
 
gm280

gm280

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Jun 26, 2011
Messages
14,605
Skeeter54 said:
Ignition cool has no spark. Stator and trigger are good. Sounds like another bad pack
Click to expand...

And I take it the pack is all inclusive so if one isn't work the entire pack has to be changed... :facepalm: Such a sorry design...
 
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Skeeter54

Seaman
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May 28, 2015
Messages
60
Yes sir unfortunately. I do have a question. I read if I disconnect the white wire connecting both and all 6 fire then the pack firing all 6 is bad because of a bad diode blocking power to #6. Sound right? Probably dumb question but if I disconnect it and they all work why not just leave it disconnected? I'm sure there's a method to the madness
 
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emckelvy

Commander
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Jan 16, 2004
Messages
2,506
If you have no spark condition in #6, the first thing to do is check the coil and not assume the switchbox (or other components) are bad.

You can swap the coil to another cylinder and see if the problem follows (bad coil) or not (likely bad switchbox). Or you can swap 2 coil output wires at the switchbox and it proves the same thing.

It's very common on these ADI motors to see coils crack, especially if they're the original orange ign coils.

Disconnecting the bias wire between switchboxes is part of the diagnostic process. The bias wire is required for normal operation.

Here's the link to the CDI troubleshooting info:

http://issuu.com/cdielectronics/doc...t.xml&backgroundColor=000000&showFlipBtn=true

HTH..........ed
 
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