Electronics International CA-1 - Manual (Page 7)

EGT's Operating Instructions
4
2. Remote Switches:
A remote switch may be connected to any channel on any Electronics International
Instrument. This gives the instrument multi-channel capability. There are two types
of remote switches available, single deck and double deck. If a single deck four
channel remote switch (RS-4-1) is connected to the EGT channel on an EC-1, the
instrument would be capable of measuring four EGT's and one CHT. The remote
switch will select which EGT channel would be displayed on the EC-1 instrument
when the instruments selector switch is placed in the EGT position. If a double deck
four channel remote switch (RS-4-2) is connected to the EGT and CHT channels on
an EC-1, the instrument will be capable of measuring four EGT's and four CHT's.
The EC-1 will select wether EGT or CHT will be displayed. The Remote Switch will
select which channel will be displayed.
EGT's
1. Leaning:
You will want to lean your engine in cruise. A rich running engine wastes fuel needlessly and tends to run
rough. This creates vibration, which causes deterioration of engine accessories and engine mounts. Also,
proper leaning at cruise and during descent means less spark plug fouling, longer life for the plugs, reduced
maintenance costs and considerable fuel savings. Furthermore, good leaning techniques result in cleaner
combustion chambers with fewer lead salt deposits on the pistons and exhaust valves. Under certain condi-
tions, these deposits invite preignition and higher maintenance costs. Proper leaning at cruise during cool or
cold weather aids in raising engine and oil temperatures to desirable minimums in order to evaporate the
water and acids out of the oil. Water and acids attack the insides of an engine, causing rust and corrosion.
To properly lean your engine using a multi-channel analyzer perform the following steps:
A. Rough Leaning: Select the hottest EGT cylinder. Adjust the mixture control from the full rich
position to a leaner setting that results in a slight drop in engine RPM or to a setting near peak EGT, as
dictated by experience. The mixture control should be left at this setting until the EGT’s stabilize. It
will take about 20 seconds for the temperatures to stabilize within 1`F. This lag is due to the combus-
tion walls and piston domes increasing in temperature, which affect the combustion and exhaust gas
temperatures. To correctly lean an engine you must wait for the engine to thermally stabilize. Less
sensitive gauges will not pick up these subtle changes, which are important in leaning and diagnosing
problems.
B. Precision Leaning: Again select the hottest EGT cylinder. This cylinder may be different than the
one you started with. This is the cylinder on which you should perform your precision leaning. Again,
start leaning, making only very small adjustments and waiting 3 to 5 seconds between adjustments. As
Instrument displaying
EGT for channel #2.