Dynon Avionics EMS-D120 Installation Guide - Manual (Page 16)

Transducer Installation
3-2 EMS-D120 Installation Guide
Exhaust Gas Temperature (EGT) Probes
Correct placement of EGT probes on the exhaust manifold is critical to obtaining accurate
readings. Placement differs between engine types, and even specific models. Consult your
specific engine’s manual for proper EGT locations.
ROTAX ENGINES
For Rotax 912 engines, only two of the four cylinders are typically monitored for EGT. Unlike
the CHT probes which are mounted on diagonal cylinders, the EGT probes should be mounted
on the two rear cylinders’ exhaust manifolds. It is critical that the EGT probes be mounted to
parallel cylinders’ exhaust manifolds for proper temperature comparison.
ALL ENGINES
Once you have determined the appropriate EGT locations for your engine, drill 1/8” diameter
holes at the specified positions in the exhaust manifold. Usually, this spot is 2 to 8 inches from
the cylinder. This spot should be on a straight portion of the exhaust manifold, as this provides a
better fit for the hose clamps. For best results, mount all probes the same distance from each
cylinder.
1. Make sure the hole is placed to ensure that the probe does not interfere with the cowl or
spark plug. Also, when making holes, keep in mind that the probe could inhibit the ability
to perform routine maintenance if placed incorrectly.
2. Place probe in exhaust manifold, and secure it by tightening the clamp with a flathead
screwdriver. Make sure the clamp is tight and provides a secure fit, but do not over-tighten
such that visible stress is put on the pipe.
Now, plug each thermocouple wire into its corresponding wire on the thermocouple harness.
Ensure that you match the wire color pairs on the harness to those on the thermocouple. All
thermocouple harnesses supplied by Dynon have each function (e.g., CHT1, EGT1) labeled on
each thermocouple pair.
A loose probe could allow exhaust to leak. This can lead to carbon monoxide poisoning
in the cabin and/or a potential fire. Have a knowledgeable mechanic inspect the
installation.
The probe can come lose during flight, and could potentially come in contact with
rotating engine parts or the propeller. We suggest a safety wire to keep the probe in place.