----- Original Message -----

From: Bill Bradburry

To: Rotary motors in aircraft

Sent: Wednesday, March 05, 2008 8:58 PM

Subject: [FlyRotary] Re: Renesis crank sensor users

I started the engine after I installed the circuit and ran it for a few minutes just to see if I had screwed something up in the install.  My initial impression is that the hesitation is gone and the engine runs much smoother.  The A/F ratio seems to be more stable as well.  I am working on my cowling at the present time, but as soon as I finish, I will try and get the engine tuned up and we will see how it runs.

 

By the way, I don’t have a clue as to what to expect when doing a max static rpm run.  I saw on the list the other day where someone with a similar set up, (Renesis, 76 X 88 prop Cato where mine is Performance) was getting 6000 static at a density altitude of 6000 ft and manifold pressure of ~22 inches.  My field is at 55 feet.  I haven’t done any density altitude calculations, but it is going to be close to sea level.  I am getting about 5300 at about 30 inches.

Does anyone have an opinion about how these numbers might compare?   I haven’t tried to tune it yet, but it seems to me that the rpms should be closer.

 

I also am getting a pretty good vibration when I run it up.  During the above test, for example, I could hardly read my altimeter for the vibration of the needle.  I am expecting smoothness with the Renesis.  Could this be due to the tuning?  I spoke with Clark Lydick.  The prop could be the problem, but it is probably not more likely than something else.

 

Opinions??

 

Bill B

 

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From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Wednesday, March 05, 2008 7:42 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Renesis crank sensor users

The high speed miss/backfire (which can be very violent) is the symptom you might expect to go away in your case.  The hesitation is probably unrelated.  For that you probably need to richen the mixture at the point where the engine is running prior to the throttle advance.

 

Note that if the engine is leaned out for best economy (using the manual mix control) and you then come down without setting the mixture to 'normal', the hesitation is likely.   This is the same as you might get on a Lycoming in the same situation.  Always set the mixture to moderately rich after descending or in the pattern.

 

There are several other things that can cause hesitation as well but I don't have enough info to say what your's might be.

The unstable mixture might be related but again, not enough info to go on.

 

Tracy

On Fri, Feb 29, 2008 at 5:51 PM, Bill Bradburry <bbradburry@bellsouth.net> wrote:

Tracy,

Could you please elaborate a little about some of the symptoms that you have heard or know about that this will cure?  My Renesis starts fine, but I get some rough running at speed.  I have had backfire once.  Also, when I advance the throttle, the engine does a large hesitation before it takes off in a quick rev.  Like a car might if it didn't have an accelerator pump.

My air/fuel indication seems to be unstable also at speed.  Is that related?

 

I put the circuit together this afternoon and will install it, but I am wondering what symptoms I might expect to go away… 

 

Thanks,

 

Bill B

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From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Tracy Crook
Sent: Thursday, February 28, 2008 1:15 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Renesis crank sensor users

Forgot to explain how to connect it.  The two leads are to be connected directly across the two leads of the Renesis crank sensor.  It can be installed near the sensor, near the EC2 or anywhere in between, whatever is easiest.   It is not polarized so it doesn't matter which terminator lead goes to which sensor lead.

On Thu, Feb 28, 2008 at 1:06 PM, Tracy Crook <tracy@rotaryaviation.com> wrote:

After completing a study of my 20B problems associated with the Renesis trigger wheel and sensor,  I am recommending that all users of these parts along with an EC2 engine controller install the sensor termination circuit shown on the attached drawing.

 

The Renesis sensor has different enough characteristics from the 2nd gen sensor that it needs this circuit to properly match it.  It replaces the 1000 ohm resistor that some may have already installed.   This addresses both the starting problem and the high rpm miss that have occurred in some installations.

Tracy