Page 1 of 1

EGT EGT EGT???

Posted: Mon Oct 09, 2006 5:06 pm
by Slow_Poke
Rotax 503, normal EGT, CHT readings during cruise and climb.
During a gliding descend, should EGT readings decrease / increase or stay the same? The P.T.O sides EGT increases a lot (sometimes exceeding the upper limmit) but the starter side also climbs but not as high. HELP?

Posted: Mon Oct 09, 2006 5:37 pm
by Morph
It depends on a lot of things, one of which loading on the motor, i.e. your pitch on the prop

My plane is set to max rpm of 6250 during takeoff. I have watched my EGT's and they are cooler during climb than at cruise. At cruise they are usually around 560 to 580 deg C they drop slightly on climb at full rpm.

On decent I have a hot spot at around 4200/4300 rpm where the EGT's go up to almost 600 and the engine runs roughly. My normal long cruise decents are around 4000 rpm, where the motor runs smoothly and cooler. I can't remember the exact values but I reduce the rpm below the hot spot.

I use the MGL EMS-503 engine management system with dual EGT, CHT, RPM and hobbs meter

Hope this helps

Posted: Mon Oct 09, 2006 7:42 pm
by RudiGreyling
Ditto on what morph said, higher EGT's when running leaner, typical at partial throttle settings. If you get a hotspot, change your RPM when descending. Mine is typical lower on full power, 503 on the highveld running 155 main jets. Mine peaks on extended long cruises with the hand cruise throttle set in fixed position.