Figure 4-55 Fuel Flow Overbraid; Figure 4-56 Tcm/Bendix Magneto Vent Hole; Rpm - Garmin GI 275 Installation Manual

4.7.6.1 Fuel Flow EMI
NOTE
The installation of EI FT-60/90 fuel flow sensors must be checked for EMI in accordance
with the procedure defined in Section 6.7.
If the fuel flow gauge fluctuates during the EMI checkout procedure (refer to Section 6.7), an EI FT-60 or
EI FT-90 fuel flow sensor must be installed with shield bracket and wire overbraid. Refer to Figure 4-54
for the installation that illustrates how the fuel flow sensor cover plates are shielded by the bracket (7). The
overbraid must cover the unshielded portion of the sensor wiring and must be terminated such that the
overbraid is connected to the fuel flow sensor and the shielding of the wire. Refer to Figure 4-55 for
overbraid installation.
GEA 110
~ +12V 1 EXCT 69
FUEL FLOW 1 15
4.7.7

RPM

The GI 275 system can use the electrical signal generated by the primary magneto coils or "P-Lead" to
display RPM. Both magneto P-Lead signals, left and right, must be connected to the GEA 24/110. The
connection is made at the ignition switch if the magneto does not have a ring terminal stud; otherwise, the
connection can be made at the magneto or at the ignition switch, whichever minimizes the length of wire
required to connect the GEA 24/110. The wire length between the P-Lead connection and the resistors
must not exceed 6 inches. Shielded wires must be used as shown in Appendix B.
If the P-Lead on TCM/Bendix magnetos was used, torque the P-Lead nut between 15 and 17 in-lbf. If the
P-Lead on Slick magnetos was used, torque P-Lead nut between 13 and 15 in-lbf.
This STC only provides interface approval to magnetic pickup RPM sensors. It does not provide
installation approval for magnetic pickup sensors. For TCM/Bendix magnetos, the magnetic pickup must
be installed in the vent hole furthest from the distributor cap. Refer to Figure 4-56.
190-02246-10
Rev. 11
P2
GROUND 74
s

Figure 4-55 Fuel Flow Overbraid

Figure 4-56 TCM/Bendix Magneto Vent Hole

Total Length <6"
Terminate
overbraid to Bracket
GI 275 Part 23 AML STC Installation Manual
RED
Orientation
WHT
optional
EI
BLK
FT-60/90
Page 4-75