912 Garmin EIS Sensor Kit

Hi Pascal,

The Garmin kit typically contains two, type K Thermocouple, 3/8-24 Bayonet, EGT, Alcor 86255 (Garmin p/n 494-70001-00) they are usually clamped on the exhaust header pipe with one on the front cylinders (closest to prop) and one on the rear cylinders (closest to firewall).

I thought the CHT (Coolant temp) sensor came with the Rotax engine? Most installs seem to have the EGT sensors fitted on the cylinders that don't have the coolant temp sensor so you have at least an EGT or CHT sensor covering each of the four cylinders.

My understanding behind only two EGTs is given the fuel/air mixture is not adjustable in flight and the cylinders on the same side of the engine share a common carburettor (1&3 and 2&4 are common) also the common intake manifold its very likely the EGTs are going to be quite close and similar on that side of the engine so one EGT per side of engine is enough.

If your EIS LRU is something like the Garmin GEA24 there is nothing stopping you buying some extra sensors and wiring them in, the GEA24 as an example has plenty of spare cylinder temp inputs for a Rotax.

The Garmin sensor kit is already quite expensive IMO (as is everything in aviation!) so perhaps some effort has also been made to reduce the cost of the sensor kit.

Thanks a lot for your Info Byron. Thats a good explanation. As we would like to use Engine Data monitoring and sending data to Savvy we were curios, if it would give even better data to each single cylinder, if we would have four probes each...