Maintenance Inspections
Teledyne Continental Motors, Inc.
TM
7-14
IOF-550 Permold Series Engine Maintenance Manual
1 April 2007
cylinder head temperature (CHT) of 300 to 350
°
F (149 to 177
°
C) is observed on the
aircraft gauge.
For aircraft fitted with constant speed propellers, operate the engine at a high enough
power setting to allow the cycling of the aircraft propeller. For aircraft with fixed pitched
propellers, operate the engine at full static RPM.
WARNING
The fuel must be shut off prior to Differential Pressure Testing
to prevent accidental engine starts. Take necessary precautions
to prevent accidental rotation of the propeller while
performing this test. Differential pressure tests are best
performed with two people, one to adjust the pressure
regulator and one to hold the aircraft propeller.
Purpose
The “Master Orifice” is a calibration standard that must be used prior to performing the
Cylinder Differential Pressure Test. The Master Orifice establishes the acceptable
cylinder pressure leakage limit for the test equipment being used and the atmospheric
conditions at the time of the test. The acceptable cylinder pressure leakage limit reading
must be recorded along with the individual cylinder readings in the engine logbook and
the inspection work order.
Frequency
Prior to performing the Cylinder Differential Pressure Check
There are two types of differential pressure testers and a corresponding setup procedure
for each tester to establish the calibrated master orifice baseline. Refer to the procedure in
the following pages that corresponds to the tester being used to perform the cylinder
differential pressure test.
7-3.8.2.1. Differential Pressure Tester E2M setup
To establish the acceptable pressure leakage limit for a Model E2M Differential Pressure
Tester equipped with a Master Orifice Tool, perform the following procedure:
Procedure
1.
Set the Master Orifice Valve to the OFF position. (The handle is horizontal and
directly over the OFF label).
2.
Set the Slow Fill Valve (next to the pressure regulator) to the OFF position; handle
vertical and pointing down.
3.
With the Slow Fill Valve OFF, connect the air source to the tester at the male quick
connection fitting.
4.
Adjust the pressure regulator so that the left hand gauge reads 80 psi.
5.
Set the Master Orifice Valve to the TEST position. (The handle is vertical and
pointing down).
6.
Open the Slow Fill Valve completely (handle pointed up beside the PRESSURIZE
label).
