High CHT's only 70 hrs, Why?

Mike Hockett

Mike Hockett

Filing Flight Plan
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Aug 10, 2019
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MikeH N551MH
Right after I got my 2018 Searey back from progressive aerodyne for its first annual a couple months ago, I noticed my CHT would be in the yellow or red on departure. I only have 70 hours on the aircraft and can't figure this out. during the annual, they also did the throttle forward conversion. I was aircraft #1. Any clues?

I never paid attention before, but during level flight and 4,900 RPM, the CHT usually holds in the green at 195. Oil temperature also holds about 190 to 195 and or pressures in the green. Is that a normal cruise flight CHT temp?
 
If this is something that changed, from the service, then, simply, something is wrong.

Baffling re-installed incorrectly?
Timing Problems (as suggested)
Fuel delivery problems, from the conversion, causing a lean-running condition?

My money is on baffle/airflow issues, but I'm just staring at a Magic 8-Ball.
 
I assume you have a Rotax (water cooled heads). If so, look for things around the radiator that may have changed. Did they change coolant from Dexcool/water to waterless?

Did they eff with the carburetors (if you have them)?

It's hard to change the timing on a Rotax.

You may wish to tell us what kind of Rotax (carbureted? Injected?) and what the throttle forward conversion involves.
 
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Being in the red isn't normal - obviously, but the question was cruise flight being at 195 (in the green). I checked 2 other photos showing cruise flight and the gauge is clearly below 160, so something had to have changed. I'm running the Rotax 914 (115hp) turbo fuel injected.
 

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Well then now that you told us more info...just ignore everything I said. o_O
 
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