JOAP ATOMIC EMISSION ROTRODE

NAVAIR 17-15-50.3

TM 38-301-3

T.O. 33-1-37-3

CGTO 33-1-37-3

ENGINE:

TF41-A-2/-2A/-2B/-2C/-400/-402C/402D(NAVY ONLY)

AIRCRAFT:

(A-7A/-7E/-7F/-7H)(EA-7L, TA-7C

JOAP ATOMIC EMISSION ROTRODE

Abnormal Trend

Normal Range

*0-10

*0-6

Marginal Range

*11-12

High Range

*13-15

*8-9

Abnormal

*16+

*10+

Average Concentration Other Elements:

Mo=2 All others less than 1.

Si=15

Sn=10

TI=1

NOTE

Under criteria table: *use lab advice code F in any case where TF41 engine oil samples have critical

wearmetals at the upper limit of normal range or above and/or if the trend is abnormal. Other appropriate

codes may be used after the code F recommendation.

NOTE: 1. Caution must be exercised when evaluating this engine due to high oil consumption and small oil

tank capacity. Use of decision tables alone as a basis for evaluation may be misleading. Trend

analysis must be utilized to successfully evaluate this engine. It is also recommended that test results

be plotted on graphs to assist in evaluations. A developing trend may be indicated with increases of

one or two PPM in one or more elements. If a developing trend is suspected by small increases of

wear metal (s), one or two PPM, maintain close surveillance. DO NOT REQUEST DRAIN AND

FLUSH. Use the next sample to confirm past results. If the suspected developing trend is 3 PPM or

greater in one or more elements, immediately notify maintenance NOT TO ADD OR CHANGE OIL and

request a check sample after 30 minutes ground run. If a trend continues to develop, in either situation,

notify the propulsion branch chief and recommend positive maintenance action be taken.

NOTE: 2 Use lab advice code F in any case where TF41 engine oil samples have critical wear metals

exceeding the normal range.

NOTE: 3 High silicon indicates contamination probably due to sampling error. However, consistently high

silicon of 30 PPM or more indicates contamination. Flush oil system in accordance with NAVAIR 02B-

5EA-6-1 or NAVAIR 01-45AAE/F-2-4.6 and sample after five hours of operation to ensure silicon

removal.

NOTE: 4 Increases in Cu by itself may indicate defective bearing. Increases in Cu accompanied by

increases in Fe may also indicate abnormal bearing wear and /or seal ring wear. Increases in Cr by

itself in any amount may indicate rotation of no. 6 bearing outer race in housing. Increases in Cr

accompanied by Fe may indicate piston ring seal wear and could result in excessive oil consumption.

Increase in Al may indicate fretting internal gearbox cover and /or oil pump. Increases in Mg may

indicate abnormal wear in high speed gearbox.

A65