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cainbird
01-15-2011, 06:38 PM
I am getting ready to wire my engine and was wondering if anyone has an aluminum ignition box like I do. I was wondering whether to mount it on the front or rear of the firewall. I was also wondering if there have been problems with having the coils and all in a box like this. Seems like all the pictures I see show most people mount the coils on the top of the engine without a box like this. Thanks~Cain B1916

DesertFox4
01-15-2011, 08:00 PM
cainb- that is an ignition box off of a very early 912 80 hp. I had the same thing in my model 3 that was finished and first flown in 1991. It now has over 1850 hours on it with no problems. I moved mine from inside the cockpit to the engine when I had to pull my engine to weld a broken motor mount. It was a pain having to finagle it through the special hinged opening the builder had to make in the firewall. Thus the reason I relocated it to the engine like the modern ignition modules.
Rotax now mounts all ignition systems on top of the engine.

HighWing
01-16-2011, 09:42 AM
Just a suggestion. The wire in the nodule is not the Tefzel insulated wire that we are used to. I am personally aware of several wire failures in the modules due to engine vibration. We did a field repair once with a butane soldering iron after a friend lost one side of his ignition in the remotes if Idaho. Also, the standoffs that support the module on the engine broke twice on my own Model IV. Many have moved the module to the engine mount (firewall side of the rubber) or the firewall. The ignition wires are much better able to absorb the vibrations.

cainbird
01-16-2011, 11:32 AM
Thanks for the replies guys. Sounds like mounting on the engine side of the firewall would be best, If I can find a spot big enough. Seems like a neat tidy little ignition box, I wonder why they stopped using them. Seems a lot cleaner and more protected from the elements than just mounting them on top of the engine which seems to be the most common meathod these days.

sdemeyer
01-18-2011, 11:05 PM
I have lost track of the number of times I've taxied to the end of the runway, only to turn around and taxi back because of broken module wires. Partially due to crappy wiring job and partially due to the constant subjection to engine vibration. The very first thing I am changing when my KF goes in for restoration is moving the modules off the engine and onto the motor mount.