912 ignition issues

[avidflyer]

Tried more combinations of stuff today, and module 2 ran coils 3 and 4 with either 4pin connector coming from the engine. Module 2 would not run coils 1and 2. Module 1 ran no coils with either 4 pin connector hooked to it. Tried third module I borrowed from a different 912, and it ran coils 3 and 4 but not 1 and 2. Judging from this, it seems module 1 and coils 1 and 2 have issues. More testing tomorrow. I'll try two different coils and the third module, and maybe I'll have 8 plugs firing. Hope anyway. I'll also check for broken wires on module 1 and the bad coils. I think all the grounds are good, cause I built a new mounting system for the coils and modules and they bolt to the engine and the ground wires are fastened with those same bolts. Progress though. Anything that moves the process forward. Any thoughts on a diagnosis from anyone? JImChuk

[WWhunter]

Jim,
I went through a rough time with mine also when I first purchased t. It ended up being a wire that comes up from the stator. It was a bugger to find since it was inside the SS braided line. I found 2-3 breaks in the wire (inside of its insulation) I patched the broken areas but believe I am having the issue again. One module is very intermittent and I may just need to replace that bad wire this time. Unfortunately, I'm going to have to pull the engine off to get to the stator.

[avidflyer]

I wonder how hard it would be to replace the wires completely inside the stainless braid? Everyone says the wires break and cause problems, if the wires were replaced with good quality ones, that problem should go away. I know it would be real difficult with the modules, cause if the wire is broke next to or just inside the module, how do you fix that. Different if you can go right to the pick up coil and install another wire. Not sure if that's possible either, but it's worth a try maybe. At any rate, in my case, it seems that the problem starts further down the line, one module and the coils. JImChuk

[avidflyer]

Last update for now. I have 8 sparkplugs firing and I'm happy for that. This is what I found. I had one bad ignition module, one broken wire from the charging coils, and a broken ground wire on the one coil that was giving me problems. When I went to remove that coil, as I was unhooking the ground wire, it pulled off, and just a little bit of insulation was holding. Glad I got to the bottom of that. I swapped out the bad module for one off another engine. After I was all done and knew it was running right, I put that bad module back on just to be sure, and right away, I lost that mag. I think it's possible that the broken wire from the charging coils was on it's last legs, and maybe broke in the moving it around as I swapped modules and stuff. I think maybe the ground wire was the start of the problem originally. I'm going to get new spark plug wire and move the coils and modules up onto the airplane side of the motor mount. For now though, it can sit on the bench while I work on the panel and firewall and such. Thanks to those who offered suggestions. JImChuk

[WWhunter]

Awesome!! Glad you got it figured out. So, when can I expect you to fly down and figure mine out?

[avidflyer]

Trial and error Keith, trial and error. Just keep swapping parts and keep notes on what works where. And check the ground wires! :-) JImChuk

[WWhunter]

Thanks Jim! Unfortunately I don't have any 'spare parts' laying around to swap out and use for deducing the problem. I did have that Model IV, but it was sold so now all I have is the one Rotax powered flivver.