JOAP ATOMIC EMISSION ROTRODE (Cont)

NAVAIR 17-15-50.3

TM 38-301-3

T.O. 33-1-37-3

CGTO 33-1-37-3

ENGINE:

F101-GE-400 (Cont)

AIRCRAFT:

(F-14B) (F-14D)

1. A sudden increase (9-11 ppm for emission) of Fe may indicate main bearing distress; small amounts or Ag

may accompany the Fe.

2. A moderate increasing trend of Fe may indicate excessive wear of gears and gearshaft splines.

3. For a confirmed significant (8-9 ppm) Ti reading, the Nos. 1, 2 and possible No. 3 bearing inner races may be

turning on the inner race journals.

4. Lube and scavenge pump bearing distress may be indicated by trends in Fe and Cu together. Al may

accompany the Fe and Cu.

5. Increasing trends in Fe may indicate gearbox problems. Al and Ag wear metals may accompany the increase

in Fe.

6. Cr is used on Nos. 4 and 5 bearing journals and may be used for repair of gearbox bearing journals. Increasing

Cr may indicate inner race spinning on the journals.

7. Inspect chip detectors when increases in JOAP wear metals cause concern; debris in the chip detector may

indicate part distress.

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

are detected by chip detectors.

9. High Si indicates oil contamination, possibly from the oil servicing cart, engine wash chemicals, or hydraulic

pump torque motor servo valve damping fluid. High Si content in oil sampled from the Hydraulic Pump with

Normal Range Si content in the oil sampled from the Lube and Scavenge Pump oil would indicate leakage of the

Hydraulic Pump Torque Motor Servo Valve damping solution, Hydraulic Pump replacement is recommended.

The oil-servicing cart should be checked for contamination and, if contamination is confirmed, shall be drained

and flushed. The engine shall be drained and flushed to remove Si contamination. Post maintenance samples

from the engine and oil-servicing cart, if applicable, shall be analyzed by the OAP laboratory to assure all Si

contamination has been removed.

10. Abnormal trend or high level of Zn is not indicative of a failure unless accompanied with an abnormal trend or

high level in Cu (fuel boost pump bearings).

11. Abnormal trend or high level or Mo is not indicative of a failure unless accompanied with an abnormal trend or

high level in Fe and Cr.

12. When high levels of Fe or Cu are noted, additional oil samples should be taken from the hydraulic drain port

on the oil tank. This may isolate the source of wear metal to either the lube system or hydraulic system. When the

hydraulic system is generating wear metal, the wear metal concentration in the hydraulic oil sample will be

significantly higher than the wear metal concentration in the lube oil sample.

A-90