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79-31-0 May 01/98
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BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
TROUBLE PROBABLE CAUSE ISOLATION PROCEDURE REMEDY
Indicator pointer Remains at top of scale Indicator remains at zero or below Both indicators read zero Oil quantity indication changes rapidly by 3 or 4 gallons or drops to zero as engine Is run up Short in tank unit Open compensator circuit Defective indicator No power at indicator Open tank unit circuit Short in compensator circuit Defective indicator Defective test switch Defective system wiring Defective indicator Oil quantity low Defective tank probe Continuity check system wiring and tank unit Check that circuit breaker is closed and continuity check wiring between tank and indicator and between test switch and indicator Check wiring and tank unit, With pin 3 grounded to flange, Measure capacitance between Center of pin 1 and pin 2. Capacitance should be 22.30 (+ 0.30) MMF (Tank unit must be dry.) Check wiring and tank unit Continuity check system wiring. Check wire splices and Shielding on lead to tank probe Check quantity Replace tank unit Repair defective wiring or replace tank unit Replace indicator(Ref 31-00-11 R/I) Close circuit breaker or repair defective wiring Repair defective wiring or replace tank unit Repair defective wiring or replace tank unit Replace indicator(Ref 31-00-11 R/I) Replace test switch Repair defective wiring Replace indicator (Ref 31-00-11 R/I) Service oil tank Replace tank unit
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May 01/03 79-31-0
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BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
OIL QUANTITY INDICATING SYSTEM - ADJUSTMENT/TEST
EFFECTIVITY
ONE OF THE FOLLOWING CAPACITANCE TESTERS:
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SIMMONDS PRECISION 387016-1 OR 387991-003
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GENERAL RADIO CO. TYPE 1429A OR MD-1
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HONEYWELL TYPE HT-109
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CONSOLIDATED AIRBORNE SYSTEMS MODEL TF-20
1. General
A. The oil quantity indicating system adjustment/test is performed to ensure operational integrity of the tank unit, oil quantity indicator, and system wiring. Bench adjustment of the tank unit and indicator is not sufficient to ensure proper component operation after installation on the airplane.
B. System adjustment should be checked at every oil change, when a tank unit or indicator is changed, and whenever an engine is changed.
C. Four adjustment procedures are provided for the oil quantity indicating system. These procedures provide instructions for adjusting wet oil tanks with oil above 38°C, wet oil tanks with oil under 38°C, dry oil tanks in which no oil is added during the adjustment and an alternate wet tank procedure.
D. Two tests are provided. One tests the system after a dry tank adjustment by adding a measured quantity of oil and checking the indicator reading. The other tests the system insulation, a factor which may affect the stray capacitance in the system.
E. If adjustment of the oil quantity indicating system is performed more than 30 minutes after engine shutdown, ensure an accurate indication of engine oil quantity is obtained. This is necessary because oil will drain from the oil tank into the engine sump after engine shutdown causing the possibility of inaccurate oil quantity indications or overservicing of the oil tank during the adjustment or test procedure. If the oil quantity indicating system cannot be adjusted within 30 minutes of engine shutdown, all oil can be drained by opening the oil tank drain valve and removing the main oil drain plug from the bottom of the accessory drive gearbox housing.
F. When calibrated per the following procedures, the oil quantity indicator will show the usable quantity of oil in the tank. Approximately 1.3 gallons of nonusable oil in the tank bottom which will not be available to the engine or reflected on the oil quantity indicator.
2. Oil Quantity Indicating System Adjustment
A. Oil Quantity Indicating System Adjustment (Wet Oil Tank Calibration with Dry Tank Unit Probe or Oil in Tank Above 38°C (100°F)
(1) Equipment and Materials
Oct 20/90 79-31-0 Page 501
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
(a)
Any of the following capacitance testers may be used: 1) Field Calibration Unit, Part No. 387016-1 or 387991-003, Simmonds Precision Products, Inc., Tarrytown, New York 2) Variable Capacitance Tester, Type 1429-A or MD-1, with current calibration chart, General Radio Co., West Concord, Massachusetts 3) Variable Capacitance Tester, Type HT-109, Honeywell Inc., Annapolis Operation, Annapolis, Maryland (two required)
4) Capacitance - Type Liquid Quantity System Test Set, Model TF-20, Consolidated Airborne Systems Inc., Carle Place, Long Island, New York 中國航空網(wǎng) m.k6050.com 航空翻譯 www.aviation.cn 本文鏈接地址：737 AMM 飛機(jī)維護(hù)手冊(cè) 滑油 OIL(13)
