Jeff
I fiddled with Jab 6 baffles and plenums for weeks. Finally Tony Higgins
told us to put a box below the air filter plenum to give non curving
airflow into the mouth of the carburetter. That cured the very uneven
CHTs instantly. It seems all the cooling problems were caused by uneven
mixture distribution from the single carb on the Jab. Tony never says
anything on here unfortunately.
Graham
JEFF ROBERTS wrote:
> Since I struggled with the cooling on my 912-S Tri gear for so very
> long I thought I'd throw my thoughts into this subject. I have found
> the air cooling of the fins to be inadequate. If you look at the round
> inlets in relation to where the top of the engine sits you will find
> they are too low and too outside. After trying everything to get mine
> to cool on the ground and in the climb I finally got mad and took a
> drummel tool to the inlets and opened them up a bit to the top and in
> towards the spinner. For now... she looks a little sad but my CHT's
> instantly dropped about 10 to 15 degrees. I'm going to work on the
> inside of these holes next to provide an expanding 1" wall to
> eliminate any turbulence of the incoming air flow.
> Believe me I'v tried everything everyone has mentioned here from
> closing up all the gaps around the rad to closing the gills. Nothing
> did more for taxi and climb cooling than raising these holes. If you
> look at all the LSA's with rotax engines the intakes are higher so the
> air can get to the top of the engine before it's pulled or pushed down
> through the fins. The real solution would be for rotax to start
> selling plenums like the Jab's then route the hoses to fit over them.
>
>
> Regards,
>
> Jeff R.
> A258 - N128LJ / Gold Rush 130 hours and enjoying every flight more.
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