Jim, thanks for the report. Aluminum as a heat shield is not a good
idea.My first straight exhaust cracked all over in the second hour of
running.
If I did not have a stainless heat shield, its likely I could have
burned something or worse? I always use 0.016 gauge stainless for the
heat shields.
Try running your engine at night at full throttle with the cowling
off. You'll be surprised :)
What RPM are you running on TO?

Bulent "Buly" Aliev
FXE Ft lauderdale, FL
http://tinyurl.com/dcy36

On Nov 26, 2006, at 5:32 PM, James Maher wrote:

> Yesterday I finally got around to the post 1st flight inspection on
> my Delta.
> Checked all the controls, skins, airframe stuff and then removed
> the top cowl.
> Everything looked great until I got to the muffler.
> The muffler was fine but the heat shield between it and the intake
> manifold was MELTED!
> About a 4" x 4" hole directly above the center of the muffler with
> gobs of aluminum slag in the bottom of the cowl.
> I believe that the heat shield got hot enough to droop and then
> contacted the muffler surface and was history after that.
> It's a good thing that the plenum (also aluminum) did not melt and
> get sucked into the intake.
> That would have ruined my day.
> I fabricated another piece of alum and wrapped it up around the
> plenum this time to prevent it from contacting the muffler.
> This is a temporary solution at best.
> I have an idea for a more permanent one but did not have the
> material on hand at the time.
> With temporary fix completed I proceeded to fly the second test
> flight.
> The OAT was 60F, 10F degrees higher than the first flight and the
> engine acted accordingly.
> The coolant was up to 212F and stable by the end of the runup.
> Luckily the oil was only about 170F so I proceeded to takeoff.
> Climbing out at 110-120MPH the coolant temp was 212F with the oil
> coming up.
> After level off at 3000 feet the coolant eventually came back down
> to a more comfortable 190F with the oil about the same.
> My eyes were almost glued to the EGT though, because I was
> concerned about another meltdown. The highest EGT that I noticed
> was about 1580F.
> I kept the mixture a little richer than last time hoping to keep
> the temps down.
> After circling the airport for over a half hour I decided I better
> land, as the I was loosing the sun again.
> I turned base and final too short, so I was high and fast (flying
> the pattern at 120MPH takes a little getting used to),
> But I did have 9000 feet of runway below me so I managed to get it
> down but not in the first 3000 feet like last time.
> It was more like the second 3000 feet.
> Any other airport it would have called for a go around.
> But it wasn't a bad landing and I didn't break anything.
> Didn't have time or light to look under the cowl after this flight
> as it was already well after 4:00PM ( I hate standard time).
> Can't wait to get the airplane back to it's home airport.
> An hour and a half is just too far to drive.
> Jim Maher
> Dyke Delta N11XD 13b (2.1 hours flown)
>


--
Homepage: http://www.flyrotary.com/
Archive and UnSub: http://mail.lancaironline.net/lists/flyrotary/