Good coil, no spark to the plugs

Energy One

cowbelltenors

New Member
Alright, I have been searching the forum for a couple days now trying to troubleshoot my starting problem but I am not having any luck. My 06 K9 sat for about a week after running just fine and now it just turns over with no spark. I am getting gas and have good compression but when I tested my plugs I don't see any spark. I got new plugs and tested my coil against a new one and it is fine.
I keep reading about checking the cam sensor but I can't find anything about that in my manual so I am not sure where it is.
If someone could point me in the right direction, it would be much appreciated.
 

ChoppaNoob

Active Member
Are u not getting spark to either plug ? I would guess ignition or crankshaft sensor. Get a schematic for your ignition system and ohm out the wiring first. I just went through this with mine. Others will be able to help with model specific info. If your bike uses a crankshaft sensor like mine, it is up front down by the motormount plate. Heres a shot of a bulldog with one.

 

cowbelltenors

New Member
Awesome, thank you for the picture and yes, I do not have spark to either plug. I checked the crank sensor and it looks fine. Is there something specific I should be looking for on it? And I think I saw a post about testing the ignition system.
 
Awesome, thank you for the picture and yes, I do not have spark to either plug. I checked the crank sensor and it looks fine. Is there something specific I should be looking for on it? And I think I saw a post about testing the ignition system.
This is just my guess, but if u dont hav spark to either plug, then how bout the coil? Also, im not sure how yours is since mine is a older model, but mine also has a fuse connection at the battery. It cud be the fuse or possibly the coil.

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cavcom278

THE COMMOMAN
How do you test the cam sensor to make sure that is the problem.
1. Disconnect the cam sensor from the ignition module.
2. Take out your trusty multimeter and set it to the RX1 scale.
3. Now while touching the sensor backing plate with the negative meter lead touch the positive meter lead on each of the three wires of the sensor connector (red, black, & green). If you get continuity from the backing plate to any of them the sensor is bad.

If it passes the first test...
1. With your meter still at the same settings touch the positive meter lead to the green wire and the negative meter lead to the black wire. If you get an "open" it's good.
2. Then take the positive meter lead and touch the black sensor wire while touching the negative meter lead to the green wire. In this case an "open" is bad. A reading somewhere around 300 - 750 Kohms is what you're looking for.
 
Awesome, thank you for the picture and yes, I do not have spark to either plug. I checked the crank sensor and it looks fine. Is there something specific I should be looking for on it? And I think I saw a post about testing the ignition system.
Yes, please replace your spark plug wires and all your problems will be over with. Question: If your coil is good and you have new spark plugs but your chopper won't fire up, why not? Answer: Replace the spark plug wires. Reason: Coil sends electricity to spark plug but if the spark plug wires are no good then electricity can't get to the spark plug because spark plug wires are bad. A spark plug wire (especially with Big Dog's high compression S&S 117 cubic inch engines) must have at least 40 ohms of resistance per inch of wire to create a strong enough spark to energize and keep the engine running. This happened to me and my 07 Big Dog K-9 last weekend and after going thru all you're going thru I finally bought new ACCELL spark plug wires that originally came with my BDM K-9. Pretty simple and inexpensive fix.

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chubs

Guru
Just out of curiousity, how do we know the coil is good? If the coil is good, you should be able to fire the plug with a piece of regular wire between the coil and plug, I would think. How did you check the coil? (I'm just trying to learn something here)
 
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