Jeff,

 

I suspect that  you are directing all the air at high speed thru the first 3-4 inches of your radiator without using the rear foot or so of the radiator.  I suggest you smooth out that pinch off you have at the entrance of the radiator to allow pressure to build back there and then flow thru the radiator.

 

Also, what are you doing with the right nostril of the plane?  Are you using it for anything?  Can you bring a scat tube from that right nostril to enter your plenum just about where it is pinched off now?

 

Bill

 

 

More attachments of intake plenum removed …  Jeff

 

 

Actually I don’t have any really good pictures because I took it apart … but attached is a side-view after removal of the inlet diffuser on top and also a sketch of approximate scale and shape of what I tried to make, (I don’t have a damper plate or cowl flap yet).  The top shape isn’t quite right; needs to be pinched more at the rear, also am considering a turning vane to direct more air through the front half.  Trying to make air bend 90 degrees twice isn’t easy but I chose this orientation because of the desire to add a damper at the output for winter operations.  I could drop the rear of radiator and bring air in through the bottom, spilling out over the engine but would lose the ability to have a damper – I don’t like the idea of inlet dampers.  On top of it all, my climb speed is usually only 90 mph; I don’t have the ability to get extra pressure from increased airspeed.   P.S. the radiator is the Griffin 2-58185-X, same as several other installs on this list.

The top plenum was out in the SUV; hopefully more attachments in next post …

Jeff

 

From: David Leonard <flyrotary@lancaironline.net> Subject: Re: [FlyRotary] Return to Flight - 2 Date: Fri, 15 May 2015 09:48:38 -0700 To: Rotary motors in aircraft <flyrotary@lancaironline.net>

Sorry to hear that Jeff.  My apologies if you have already posted pictures of the your installation and the diffuser, but could you post some now?   Dave Leonard   On Fri, May 15, 2015 at 8:19 AM, Jeff Whaley <flyrotary@lancaironline.net> wrote:

 

Well, the second flight occurred last night with same results as before; one short low-level circuit due to insufficient cooling … looks like Al Wick made the correct prediction.

There are 3 things I can try with the current configuration: 1) Increase inlet area 2) Increase outlet area (adjustable cowl flap) 3) Re-profile the pinched diffuser.  I will do all 3 and see what happens.

If all of the above show remarkable improvement then repositioning the radiator is the only alternative.

Jeff

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