Electronics International CA-1 - Manual (Page 13)

Installation Instructions
10
2. CHT Probe Installation
H. If this instrument is to replace an existing unit in the aircraft, it is the installer's responsibility to move or
replace any existing instruments or components in accordance with FAA approved methods and procedures.
The following Installation Instructions do not cover moving or the removal of any existing instruments or
components.
2. CHT Probe Installation:
A single CHT probe should be placed on the hottest cylinder. In a 6-cylinder engine this would be one of the
center cylinders. On a 4-cylinder engine this would be one of the back cylinders.
If a second CHT probe is to be installed it should be placed on one of the front unobstructed cylinders. This
will allow the unit to detect shock-cooling.
Most engines have a port just below the lower spark plug for the CHT probe. If your engine has a primary
CHT probe in one of the cylinders, do not remove it. Select another cylinder for your probe. If you’re
putting a CHT probe on every cylinder use our P-102 Gasket CHT Probe for secondary readings on your
primary cylinder.
3. EGT Probe Installation:
A single EGT probe should be installed in the exhaust stack of the leanest cylinder. Each engine has its own
characteristics and the leanest cylinder can be different from aircraft to aircraft. As a general rule, the leanest
cylinder is one of the back cylinders on a carbureted engine and one of the center cylinders on a fuel-injected
engine.
Look at each exhaust stack and determine the best location at which all of the EGT probes can be mounted at
the same distance down from the exhaust ports. The ideal location is 1 1/2", but ease of installation should
prevail. Drill a 13/64" diameter hole in each exhaust stack. Insert the probe and tighten the hose clamp. As
the hose clamp is heated and cooled, it will become loose as it conforms to the exhaust stack. After the first
10 hours of operation, each hose clamp should be retightened.
IMPORTANT NOTE: For Cessna 210’s or any aircraft using a slip joint in the exhaust system, install the
EGT probes ABOVE OR BELOW THE SLIP JOINT. Installing a EGT probe in the slip joint can damage
the probe.
4. Carb Temp Probe Installation:
Remove the threaded plug located in the carburetor housing just below the throttle valve. Install the Carbure-
tor Temperature Probe in this hole using a lock washer. Care should be taken not to over-tighten the probe
and strip the threads in the carburetor housing.
If your carburetor does not have a factory tapped hole, remove the carburetor from the engine. Drill out the
lead plug located just below the throttle valve with a 7/32 drill and tap this hole with a 1/4 x 28 tap. Remove
all burrs and metal shavings from the interior and exterior of the carburetor. Install the carburetor tempera-
ture probe as outlined above. Reinstall the carburetor on the engine.