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lessee,

Just a wild guess..with no basis except for a diagnostic tree-- You are having trouble with the running of your engine the injection timing and the ignition timing of which are dependent on the RPM. Separately, you are having problems with the RPM indication. Could there be a link here???
When you are having the engine problems are you also having the RPM problems?

I would look for the commonality of the systems as a clue. although the indication may be a result of the problem that is causing the bad engine operation.

Good luck hunting.

Rich

-----Original Message-----
From: Bobby J. Hughes <flyrotary@lancaironline.net>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Fri, Jul 29, 2016 9:22 am
Subject: [FlyRotary] Re: Further testing

Steve,

The attachment has everything I can remember from my on adventures and notes I collected from others. Hopefully one of the items will help. Could be a combination of two items.

Bobby

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net]
Sent: Friday, July 29, 2016 4:20 AM
To: Rotary motors in aircraft
Subject: [FlyRotary] Further testing

Hi Guys

We did further testing of the Renesis today. Would really appreciate your heads on this.
Last series of tests we had this major missing and noise which I think is fuel exploding in the exhaust.
This happens at various RPM’s based on load from the adjustable prop.
With fine pitch it would spin out to just over 7000rpm before striking this mayhem.
With medium pitch it would get to 6000rpm before the same symptoms.
From memory these were both at about 22-23 inches of Hg.
My Wideband O2 is malfunctioning at present.
The narrowband response time appears to slow to discover what the mixture is doing during the episodes.

Also still having trouble with the EM3. Sometimes display reads what appears to be an error message and at other times stops reading RPM.
The Skyview Engine monitor has the same issue at the same RPM so appears directly related.
I changed the input on the Skyview to the Standard RPM input as I incorrectly fed the injector pulse to the lower voltage input, but this made no difference.

I had wondered if the secondary injectors weren’t getting power and as a consequence when it staged to all 4 injectors the trouble began.
Using the EM3 display (staging asterisk) and switching power off to the secondaries I was able to ascertain that the secondaries appear to be functioning fine.
I did notice that the point of staging appears to be not solid.
This takes me back to Ed’s comments re damping the manifold signal to the EC2.
Sorry Ed, you might have had it right last week. I thought because it was running so smoothly up to 23 inches that it wasn’t a signal issue.
Maybe the wavelength/timing of those pulses at ~6000rpm matches the manifold signal tap position!

Ed, you mentioned either small orifice or accumulator. I estimate the volume of the signal line to be approx 18 cubic centimetres.
My gut was that the accumulator required to damp the signal would need to be an order of magnitude larger. (total guess) So maybe 180 cc’s but thats half a Coke can! Seem’s way to big.
Ed, did I understand you right that a small fuel filter can do the trick? I thought they would only be about 10 cc’s in volume.
I suppose if the pulses are very narrow/short maybe thats all to takes to damp out the pulses.

Can I ask the group please. Who had trouble with manifold signal and what was the solution that worked best.
Paul Lamar advocates tapping the signal from the oil injection ports. Has/is anyone using this solution?

Thanks very much everyone.

Steve Izett
Glasair Super II RG
Reneis 4 port EC2 EM3 RD1-C

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