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The DAR inspection went without a hitch on Friday, 04-24-15.  I took her up for the first time on Sunday, 04-26-15.  I purchased the project four years and one month ago from a gentleman that has started the build in the mid 80's.  The project was transported via trailer from Atlanta Georgia to the Houston Texas area.  From there it made its way to San Diego.  Many late nights have been spent getting it to this point.

 

The first flight went without incident.  I did see some high CHT's (490), but I attribute this to not giving it an adequate chance to cool and new "0" cylinders.  The plane was a hands-off flier.  This was my first time in the front of a canard.  I was fortunate enough to be offered back seat time in multiple.  I have been in contact with the originally owner, he is pretty stoked to stay the least.  I am looking forward to taking her through the paces. 

 

Video below.

 

https://www.dropbox.com/s/o8hzlnox767qec8/1st%20Flight%20308FP.avi?dl=0

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Good work.  Even new cylinders should not get that hot though.  500F is max for a Lycoming.  You really want to keep them below 400F.  425F might be OK for the first few hours.  Post some pics of the engine and baffles.  Maybe we will see something

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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Thanks fellas.  I went up yesterday for about an hour and circled the field at 3000.  CHT's were around 490 and I was cruising at about 135kts pulled back around 2300.  I hoping over time they decrease.  I cycled the gear a few times but mostly flew with it down.  The camera audio sounds like the motor is quickly increasing in RPM's from time to time, it is not.   

 

https://www.youtube.com/watch?v=-e5kHF-fSTU

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Kent, the 0-200 manual states that max temp is 525.  I see a lot of them in the 400-425 range in cruise.  I will get some pics of the baffles soon and post them up.  I do think that once I pick my gear up it will decrease a bit as well.  I have the NACA btw,  On descent, they did drop to the low 400's.

Edited by Rudy Davila
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Well remember that aluminum dies a little every time it is heated/stressed and it dies at lot faster at elevated temps.  Personally, I wouldn't fly it anymore at those temperatures without doing some baffle work.  You look like you're measuring on the top (hot) side of the cylinders so that will give you about 25 degrees higher CHT than on the bottom (cold side).  Still, you are running very hot.

 

Updraft cooling, right?  I don't have experience with a Varieze but those top silicone baffles (2nd pic) are a problem.  They have to flop forward to seal against the cowl.  One is flopping inside which will spill air.  In the first pic, there is not much overlap between the silicone pieces; probably leaking some air there.  Also, how about that gap on the right side where the top silicone baffle meets the black rubber baffle?  And your aluminum cylinder baffles also look a little loose.

 

Basically, any gap anywhere must be sealed.  Any gap will allow so much air to get through that it will spoil your cooling.  If your aluminum cylinder baffles are not pulled tight on the cylinders, the air will not go through the fins but through the gap and around the cylinders.  It looks like you have baffle gaps around the upper engine mount doughnuts and next to the engine below the right upper doughnut.

 

I don't see any silicone caulk either, so I know you probably have lots of small places that are leaking.   When all your baffles are tight and have a good fit, go around the edges with hardware store aluminum colored silicone caulk. 

 

If you work on your baffles and still have temps above 400-425, you might want to make a simple piccolo tube arrangement to measure the pressure differential above and below the cylinders.  Lycoming calls for 5-5.5" of water differential.  I imagine Continental needs about that.

 

Here is someone's baffles.  His sealing is pretty ugly but you see what has to be sealed.  :-)

http://www.vansairforce.com/community/showthread.php?t=26988

-Kent
Cozy IV N13AM-750 hrs, Long-EZ-85 hrs and sold

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