Electronic ignition problem - help

I'm trying to debug a problem that delayed my first flight for 2 months! I finally took the ignition off and replaced it with a magneto. I'll get through test flight and them *maybe* I'll try again.

Here's the problem....I was using a Jeff Rose system in place of the right magneto. Both ignitions were operated using a Bendix/ACS key switch. Wiring was done per the instructions.

Starting on the left mag was fine and the engine ran fine in the 'both' position. When switched to 'right' the rpms dropped over 150 rpm and the engine ran very rough. advancing the throttle would result in even more roughness.

Exchanging emails with Jeff Rose (the company has been sold to a new owner) the initial problem was though to be arcing through the plug wires. I replaced the wires and added insulating sleeves on the adel clamps. No change in behavior at all.

The next solution was replace the Bendix key switch with a new one, which I did. No change at all.

On my own I removed and replaced all of the ignition wiring, making certain that every contact was electrically good and clean. No change.

Finally I removed the unit and replaced it with a magneto. First flight was July 18th. On Michael's suggestion (the new owner of Jeff Rose Ignitions) I sent the unit to them to be inspected. They can find nothing wrong with it, and sent it back with a bill for 58$.

The only thing that they thought may be causing the problem was that the connection between the key switch and the unit (the 'P' lead connection) should be shiedled wire. I wired it with standard 18# wire - I did that to match the stub wire that came with the Rose unit since it also was 18# unshielded. And the instructions didn't call for shielded wire.

The other bit of advice I got was a strong recommendation to use toggle switches for the ignition. I chose a key switch since every aircraft, and more important to me, every emergency drill I've done in 20 years of flying has been using the key switch. So it's familiar, I prefer it.

So I'm at a loss as to how to proceed. I'd like to have the EI, however I don't have much confidence in the system. And really hate to have to remove the mag and reinstall the EI only to find it still isn't flyable.

Electonic Ignition

This might not pertain to the Rose ignition but I confess, I did it with my Lightspeed. The Lightspeed has two coils for each mag it replaces and they must fire opposing plugs. I had the plug wires going to the wrong plugs and it ran exactly how you described yours to run. Bystanders said the engine sounded not quite right on the first run, but it ran! When the coil fires it must go to an open exhaust port on the other plug that is connected to it. At least that is how I'm remembering it now. When correcting this it hasn't missed a beat since.

Bryan 9A "Flyin' the Flag"

Different System -similar problem

I won't go into a long description but my factory installed and tested electronic ignition ran very rough and almost burned up the cowl (seriously, the inside was charcoal and the outside was distorted and dark brown) because the timing was wrong - approximately 60 degrees ahead of the proper setting.

Bob Axsom

Has anybody checked the timing, and in particular the advance, on this thing? All this wire shielding/toggle switch talk sounds like voodoo to me. 150 rpm is quite a bit, especially considering the high output of an electronic unit.

Steve Zicree

Ignition woes...

I did check that the wiring from the coils to the plugs was correct. So no joy there. The timing on the Rose is set by setting the engine to TDC and the pickup unit installed using a pin to hold it in it's initial timed position until it is tightened down. The pin is removed and it is timed. So it's pretty simple.

So the timing shouldn't have been a problem.

Of course this has already been mentioned but I still bet you have your ignition wires in the wrong order. As far as timing goes you should check it with an old fashion strobe timing light. This must be done with the engine running so be real carefull of the spinning fan.

I still bet it the plug wires routed to the wrong set of plugs. I checked mine 3 times before I found that I had them wrong.

You did not mention if you are using automotive plugs. I don't know what Mike recomends for plugs but if you want to run auto plugs buy the adapters from Spruce and run the plugs Klaus Savier recomends for his ignition. I run aviation plugs (Autolite 37BY's) with my rose system and am very happy with them.

Gary

I'm not so much talking about the static timing, but rather the advance when the motor is running. If it's failing to advance as rpm comes up it won't run right and the problem will get worse the faster it spins.

Steve Zicree

EI issue

Kumhyr, I have been running the Jeff Rose ignition in the same configuration as yours for 750 hrs w/ no issues. Tripple check the plug wires.....coil A to cyl #'s 1/2 and coil B to #'s 3/4. If that checks out, then it could be the advance timing. There are 2 pots under the raised cover on the man unit. One controls idle timing and I think the other controls the advance setting which controls off MP. My book isn't at home but the new owner should be able to help on what they dhoulfd be. I seem to recall that the idle advance was 18 degrees then I THINK it advances 2 degrees for every inch MP below 24. Check it w/ the owner! You'll need a digital voltmeter and there is a test terminal on the unit. I ran that into the cockpit so I could watch the advance in flight.

Side note: I was running auto plugs, Autolite 386's but after an enlightening conversation w/ Klaus at OSH I'm changing to the NKG's to get into a correct heat range.

Jeff Farrar RV8A N4ZJ Tech Counselor