Mailing List flyrotary@lancaironline.net Message #43187
From: Al Gietzen <ALVentures@cox.net>
Subject: RE: [FlyRotary] Re: Sensors
Date: Wed, 11 Jun 2008 09:26:06 -0800
To: 'Rotary motors in aircraft' <flyrotary@lancaironline.net>

Greg;

 

Yeah; what Mark said.  Except I think I’d put them more than an inch from the port. Mine are about 2” from the port.  I have had one EGT TC failure, and one I replaced where the prob was in the EC2; but in both cases the TC extension on the inside of the pipe was slightly bent away from the port.  These are the inconel sheath, clamp-in type that extend an inch into the flow.  I conclude that the high temp and strong pulses cause them to bend a bit over time.  A little further downstream may read a bit lower, but may increase the lifespan.  (I was going to send a photo, but the batteries in my camera were dead).

 

Al

 

-----Original Message-----
From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Greg Ward
Sent: Tuesday, June 10, 2008 10:37 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Sensors

 

As long as we're at it about sensors, how about EGT?  I am turboed on the 20B, and have a 3 into one collector going to the Garrett turbo.  Do I want to have individual EGT's on each pipe, or one on the exhaust side of the turbo, or all 4?  My collector pipes are only about 8-10" before they hit the flange, so here too, I wonder where the best place is to place the sensors.   Thanks for all the input on the MAP, going to locate it close behind the valve body.

Greg Ward

Lancair 20B, details, details, details 

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

Sent: Tuesday, June 10, 2008 8:32 PM

Subject: [FlyRotary] Re: Sensors

 

I have two MAP ports on the rear of my intake plenum that feed the EC-2.  I am taking the pressure from this third port at the bottom of the manifold to the regulator.  I have a vacuum gage…I guess I should check the steadiness and consistency of all three ports. 

 

Bill


From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Al Gietzen
Sent: Tuesday, June 10, 2008 9:26 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: Sensors

Perhaps I should add that the original line from the sensing ports to the pressure regulator was quite short; maybe 10”; so there was very little damping there.

 

My fuel pressure regulator (Airmotive) is getting its MAP from the two small (1/8 “) tubes that lay in the primary ports on the Renesis…Are you saying that I should move this pressure reference to someplace else?  You say you know it is not good…How do you know this?

 

Bill B 

Bill;

 

I was measuring fuel pressure to the fuel rails to verify the EM2 calibration.  The needle on the gauge was swinging very rapidly from about 20 to 40.  I don’t recall what RPM, but I guess near idle.  Perhaps stating that “it is not good” is an overstatement, and perhaps it just happened that the pressure pulses hit a resonance in the gauge; but my judgment was that it could affect the engine operation and could be damaging to something else long term.  I had already put damping in MAP line to the EC2, so I decided to T it into that line, and the pressure pulsing went away.

 

I have a 3-barrel TWM TB on a short intake manifold.  The MAP sensing ports are just downstream of the throttle plates.

 

Al

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