Cross posted from another site, so some of you may see this twice.
I've had to let my chase plane buddy know that I'm postponing my first flight, which was to be tomorrow morning.
Turns out that on my first actual "mag check" with my dual SDS CPi2 setup, it's only running on one side. I can't believe I got this many engine runs into the project before using the A-B/L-R test function, but it's due in large part to my lack of understanding how completely the backup battery function takes over on these things - the power switches they say are required to turn it all the way off do NOT kill backup power to it and thus DO NOT substitute for a mag check done by grounding each side of the ignition by key-switch or by keypad menu entry. After I figured this out and actually did a true "mag-check" yesterday, the engine died with the key switch in the R or OFF positions but ran in L or BOTH. Same when tried with keypad. Left a voicemail at the shop 4:30 yesterday and called Barry's number later Friday evening - calls have not been returned yet. Given their reputation for customer service and my own prior experience, I know I'll hear from them at some point.
My other issue is that the ignition often lights off a charge when I first power it up. Typically it just kicks a blade back 60 degrees or so (still a hazard to anyone near the prop at that point!) but last night it fired one that sounded like a .44 mag without ear pro. Blew soot and fuel all over the floor of the hangar. Okay, I _might_ have had a hot start flooding issue just before that... This behavior is now no longer something I can ignore. A pilot should not expect an untouched prop to move by itself before cranking is begun. It's too easy to leave an ignition toggle on at shutdown and have the prop kick back the moment the Master is turned on - has already happened to me. Barry said it's a reported issue and he had a software type of fix for it but I'd have to send the CPU's back to him. Given the difficulty of access to my units and the approaching first flight target date, I decided at first to live with it and mitigate by powering up the CPU's first and then the coil packs (my left-to-right toggle sequence is LEFT COIL, LEFT CPU, RIGHT COIL, RIGHT CPU). Next time I tried this the fuel-air charge lit off as soon as I powered up the LEFT CPU with the coil pack switch still OFF!
It's obvious the unit is capable of discharging all plugs at once on power-up regardless of power/no power on the red wire to the coil pack, and one of these spark events will be on a cylinder with some residual fuel-air and sometimes an open valve or two.
What I've learned for certain is that mounting the CPU's way up under the forward skin between firewall and sub-panel was a big mistake. There were not any other attractive options I could see with the real estate taken up by the Advanced QuickPanel remote components, but I mounted them over the rudder pedal cross tubes thinking I'd never have to touch them again for the life of the airframe - and honestly, I shouldn't - but now I do. As it is, the seat and joystick must come out just to allow the tortuous yoga position needed for unbolting the ECU's from the stringers I put across the ribs from firewall to sub-panel.
I'm thankful to have found this issue before I naively launched on one ignition. I feel divinely protected from my own ignorance and folly once again.
We've seen the popping issue sometimes on installations where there are no coil power switches (coil power comes on with the master). Just had another one last week. We'll send you a new ECU to address this as soon as Barry is back from vacation on the 8th. In the meantime, you can pull the coil power breakers so this doesn't happen.
As far as the 2nd coil not firing, that could be a few things. I'll forward this to Barry and he should be able to respond today sometime by email.
I'm very sorry for the trouble here and the difficulty in getting the ECU out of there again. I'd be pissed too.
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