flyrotary@lancaironline.net Mailing List Archive

Check the basics- all of them. Are all your injectors firing? I got mine cleaned and flow tested prior to first startup. Disconnect some and run them in mode 1 to check for firing.Then repeat on the others, all separately. Check timing and TDC. YOu can get an air hold from NAPA to screw into the spark plug hole for around $6. Use this to check for minimum combustion chamber volume( TDC) Check to make sure all the plugs fire at the right time.

Brian Trubee

-----Original Message-----
From: Tracy <tracy@rotaryaviation.com>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Thu, Feb 24, 2011 7:40 am
Subject: [FlyRotary] Re: Diagnostic help please I think regarding coils/plugs EC2 etc

Hi Chris,
   It's always difficult to diagnose things at a distance when the clues are vague. The symptoms you do describe (starting better with coils disconnected, etc) don't fit any pattern I've ever encountered so I suspect something wrong in the basics.

Start at the beginning.

Do you really have a GOOD reference for TDC on rotor 1?
Are you SURE the initial static timing of the CAS is right?
If A acts differently and is now set on defaults, have you tried adjusting the timing in Mode 8?
Do you know where the EC2 timing adjustment is set on A and B?

You often mention the mixture setting and how you set when starting.   You should realize that this has almost nothing to do with the initial start.   The engine initially starts on the Primer shots you give it. If the mixture is wrong the engine will either stall or run rough but that's AFTER that initial roar from the engine. This is especially true of cold start.   Hot starts are more critical of how you prime. If you over-do it, it's easy to foul the plugs and the frustrating cycle of dealing with a flooded rotary with fouled plugs begins.   My usual advice is that if the engine doesn't crank after a few 4 to 5 second cranking attempts, stop trying and find out what's wrong. More is just wear & tear on the starter and the pilots nerves.   When the setup and procedure is right it should start in less than 1 second of cranking.

Tracy

On 24/02/2011, at 10:46 AM, Chris Barber <cbarber@texasattorney.net> wrote:

I got my engine buckled back up with the new seals and everything back on the plane.

I have gotten it to start, but, honestly, it does not seem as smooth as it has in the past.

However, the good new is, so far, it is starting much easier. Hard starting, especially when hot has been a consistent problem.

That being said, I am having some anomalies other than some rougher running. The most notable is that I was not getting the engine to start on Computer A at any mixture level, however, I would switch to B and advance the mixture to about 3 o'clock and it would start about as well as it ever had, consistently. Controller A has been reset to factory defaults, however, Controller B is set to some long forgotten settings (if I understand correctly there is not way to see the settings on B, but the fact it is starting on B at least indicates it can start). I hesitate to transfer A to B until I can get A functioning well. Once started, it "sounds" to be missing a bit. To try to diagnose it I first checked the plugs. The were installed new day before yesterday. All looked as I would expect and all have been fired so some kind of ignition event is occurring.

To try to dig a little deeper, I disconnected the trailing plugs and the engine now started on Controller A without problem. I tried to disconnect all the plugs in various manners (only front rotor , only primary , only secondary and only rear). It would start with difficulty on B with all the plugs connected, But would not start at all with just the front or rear rotor connected. I was somewhat concerned I may have been running on only one chamber, however, trying to run the engine on only one chamber with no success seems to dismiss the idea that I was only running on one rotor chamber.

I hooked up all the plugs again and now when I started I turned OFF the secondary coil switch and the engine started well on Controller A and run well. Hmmmmm . I would turn the secondary coils on once started and it would seem to run a little stronger. However, when I had both the primary coils on AND the secondary coils on when STARTING, the engine was hard to start and would not run as smoothly as when started with just the primaries and then turning the secondary coils on.

If I remember correctly , the primary and secondary plugs spark at the same time with the RWS Controller, however, it seems almost as if the secondary's are "fighting" the primaries. Like I mentioned, the A controller was reset to factory settings following my lasts assembly .

Am I triggering any thoughts. What am I missing. What next diagnostic would you guys/gals suggest? Yes, I have verified the spark plug wires are going from the correct coil to the correct plug. When I hooked all the plugs back up I slightly moved around the plug wires, I had the two front rotor wires crossing over my B lead to my alternator so I gave these wires more separation . It seemed to have helped the roughness a bit. I am likely to buy new and better plug wires tomorrow as the ones I have have been around awhile and were not the highest quality as I was in a base development stage at the time.

Since the list has been soooooo quiet as of late, other than my posting of my bent apex seals I am supposing that y'all have plenty of time to give this latest issue some thought.....unless of course you have all been out flying, thus not posting ;-)

Thanks guys, I do feel a little closer today.

Chris