F-100 DECISION MAKING GUIDELINES

NAVAIR 17-15-50.3

TM 38-301-3

T.O. 33-1-37-3

CGTO 33-1-37-3

F-100 DECISION MAKING GUIDELINES

1. Engine teardown or surveillance is required for any of the following:

a. Any wear metal exceeds the abnormal limit. Teardown is required.

b. Fe or Ti increase by the value of their abnormal trend within a 10 hour engine operating period (total

operating time). Surveillance is required for 10 hour total operating time.

c. While on surveillance for Fe, Fe increases above the value that caused surveillance by any amount.

Teardown is required.

d. While on surveillance for Ti, Ti increases above any other sample taken during surveillance by the

abnormal trend value. Teardown is required.

e. Fe increases by the single sample jump limit (5 ppm or more between any two consecutive samples.

Teardown is required.

f. Fe increases by the No. 4 bearing teardown limit (9 ppm or more within a 10 hour period. Teardown of

the No. 4 bearing is requied, unless positive identification of another wear source can be made.

g. All engines which have been disassembled for inspection due to Fe limits being exceeded. Surveillance

is required for 10 hours total operating time.

h. Cobra II limits in abnormal range or increase of 3 or more within a 10-hour engine operating period or

less from previous Cobra II reading.

2. Any sample value which requires the engine to be placed under surveillance or requires teardown shall be

confirmed by a reburn. Proper engine personnel shall be notified immediately. When an engine is put on

surveillance, request for oil filter and chip detector inspection should be made. When an engine is on

surveillance, all chip detectors are to be checked each time an oil sample is taken.

3. When a F100 engine is on surveillance, oil samples must be drawn after each flight and analysis results

must be known before the next flight. All chip detectors must be checked each time a sample is drawn. During

ground or test cell operation of an engine on surveillance, oil samples must be drawn at intervals no longer

than one hour total operating time. After an oil sample is drawn, the engine may not be run for more than one

hour before oil analysis results are available.

4. When silicon (Si) reaches or exceeds 15 ppm, drain and flush the oil. Also change the oil pressure

transmitter if PN4039126; not required for PN4059195.

5. The main engine bearing may fail without indication reflected in the JOAP analysis. Spalling of these

bearings is detected by chip detectors.

6. If the oil sample appears noticeably darker than normally observed on a specific engine, notify proper

engine personnel of condition.

NOTE

A burnt oil condition is typically, but not always, accompanied by a darkened oil

color and obvious burnt odor. The condition is generated by a local heat source. A

burnt oil condition cannot be detected by an atomic emission rotrode oil analysis

spectometer.

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