I have been working on an issue for three weeks now, with very intermittent spark when cranking the engine.  Needless to say, it won't start either.
I have a spark plug out of each rotor, and have them clamped to a good ground, so that I can see a spark on the front and rear rotor.
If i rotate the CAS by hand, or turn the prop by hand, I get good spark. When cranking with the starter, I get an initial spark, and then an occasional spark on the front or rear rotor.  Interesting, when I let off the starter, I get a couple of good sparks as it coasts to a stop.  Both controllers do the same thing BTW.

I had emailed Tracy, as at one time I thought that the EC-2 had an issue. Tracy said that he had seen this symptom a couple of times before, and it is caused by noise from the starter interfering with the CAS signal.  He suggested that I install a 1K resistor across each of the crank angle sensors.  I installed the resistors, but it did not cure the problem.

This morning, determined to get to the bottom of this, I removed the battery cable running to the starter, and using a spare battery, and a jumper cable for the ground, I cranked the starter with this battery, which was isolated from the airplanes electrical system.  It had good spark on both rotors .... yeah !!!

So then, I decided to reroute the starter cable on the other side of the engine, which keeps it away from the other wiring.  I hooked it back up to the aircraft battery, crossed my fingers and cranked the started.  Same problem.   I thought that perhaps the noise was getting into the EC-2, so I put the spare battery in the back seat (pusher aircraft), and using some jumper clips, I hooked the EC-2 through a fuse to the isolated battery. Same problem.

I had extended the CAS wiring when I replaced the engine, so I decided to reroute the shielded CAS wiring, so that I could eliminate the unshielded wires, which were about 12" long.  Same problem.

I am struggling with what to try next.  This problem started before I swapped the engine, as it was very hard to get started, though for three years prior to that, I had no issues, and it started easily.

Has anyone else seen this type of problem, or have any suggestions ?

Steve Brooks
Cozy MKIV 13BT


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