(g)  
Check engine casing flanges for cracks or loose bolts.

(h)  
Check fire detectors for unbroken seal, correct temperature rating, security of mounting and of electrical leads, and wiring for chafing and condition.

501 Feb 01/95 71-00
Page 607
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.

2.  Engine Windmilling
A.  Inspect all engines which have windmilled as a result of shutdown in flight.
B.  If there has been a continuous positive indication of oil pressure (10 psi or higher) following shutdown, the engine may be continued in service after a satisfactory inspection of the main oil strainer and chip detectors (if installed) following servicing of the engine and a ground run-up.
NOTE: Ground run-up cycle consists of five minutes at idle and normal shutdown.
Chip detectors are optional equipment. If they are installed on the engine, inspection of them is part of the windmilling check procedure.
C.  An engine windmilling for 30 minutes or less, with less than 10 psi oil pressure after shutdown, may be continued in service after satisfactory inspection of main oil strainer and chip detectors, servicing, and ground run-up.
NOTE:  Due to gage error, oil pressure readings of less than 10 psi should be regarded as zero oil pressure.
D.  Engines windmilling more than 30 minutes, but less than 60 minutes, with less than 10 psi oil pressure after shutdown, may be continued in service after satisfactory inspection of main oil strainer and chip detectors, servicing and ground run-up.
(1)  Repeat oil filter and chip detector check after first flight, 15, 50, and 100 hours. At each check, draw oil sample for test of iron content, starting with post windmill inspection.
E.  Engines windmilling for more than 60 minutes with less than 10 psi oil pressure after shutdown shall be sent to overhaul for bearing inspection. Particular attention must be given to No. 2, 3, 4, and 5 bearings.
NOTE:  Operating conditions prior to and after interruption and windmilling should be accurately recorded to determine classification of windmills.
Bearing cages must not show excessive wear. No ball and roller skidding or loss of hardness and shape due to overheating is permitted. Satisfactory bearings may be continued in service.
CAUTION:  ANY POWER ON OPERATION AT OR ABOVE IDLE WITH OIL PRESSURE OF 10 PSI OR LESS SHALL REQUIRE THAT THE ENGINE BE SENT TO OVERHAUL FOR BEARING INSPECTION.
F.  If oil supply was shut off or interrupted for more than 10 seconds at speeds in excess of windmilling or before engine decelerated to windmilling speed following engine shutdown, record conditions of operation and send the engine to overhaul for bearing inspection. Particular attention must be given to bearings No. 2, 3, 4, and 5.
NOTE:  Interrupted oil flow is less than 10 psi oil pressure.
501 
71-00 Page 608  BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  May 01/01 

POWER PLANT (JT8D) - CLEANING/PAINTING

1.  Engine Cleaning
A.  General
(1)  
Intensive mass airflow of the engine tends to cause build up of contaminants on the blades and vanes of both compressors and turbines with consequent deterioration of engine performance, i.e., high power stalls, increases in N1, N2, EGT and fuel flow. Internal cleaning of the engine is recommended on a regular basis to remove contaminants. This cleaning is accomplished by motoring the engine with the starter and spraying water or optional detergent wash solution into the engine. You must clean the engine if the engine had a fire and fire-extinguishing agents were used.

(2)  
The frequency of cleaning or the desirability of using the optional procedures listed should be determined by each individual operator, since environmental conditions vary widely among operators.

(3)  
Four cleaning procedures, which vary somewhat in complexity, are presented. These are:

(a)  
Engine Water Wash Procedure outlined in par. D. This procedure is intended as a routine preventive maintenance procedure and when performed as a regular and periodic program will serve to prevent contaminant build up and retard turbine sulfidation.

(b)  
Turbine Water Wash Procedure outlined in par. E. This is an alternate procedure to par. D used primarily to retard turbine sulfidation.

(c)  
Engine Detergent Wash Procedure outlined in par. F. This method is optional to the water wash method of par. D and is intended to remove more extensive contaminant build up.

(d)  
Engine Gaspath Cleaning After Use of Fire Extinguishing Agents outlined in par. G.
　
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