(12)
 Do the Component Check for the Center Hydraulic System (Fig. 617).

 S 796-345

 (13)
 Do the Internal Leakage Check of the Center Hydraulic System - Yaw Damper, Autopilot and Stabilizer Trim (Fig. 618).

 S 796-346

 (14)
 Do the Internal Leakage Check for the Center Hydraulic System -Lateral Flight Controls (Fig. 619).

 S 796-347

 (15)
 Do the Internal Leakage Check for the Center Hydraulic System -Empennage Flight Controls (Fig. 620).

 S 976-348

 (16)
 Center System Leakage Summary Sheet

 (a)  These are the conditions which you can use to make a decision about which components to replace. 1) If the leakage flow value of a rudder PCA is 2.0 GPM or
 more, you must replace the PCA. 2) If the leakage flow value of an elevator PCA is 1.0 GPM or more, you must replace the PCA.
 3)  If the total NULL leakage is more than 4.5 GPM, you must replace the PCAs with high leakage until the total NULL leakage is less than 4.5 GPM.
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MAINTENANCE MANUAL

 (b)

(c)

Use the Summary Sheet as follows:
 1)  For each component on the summary sheet, find the leakage flow value on the figure and step number shown below the component name.
 2)  Write the leakage flow values on the summary sheet opposite the component name as follows: a) If the leakage flow value is zero or a negative value,
 write the value in the SEAL column. b) If the leakage flow value is a positive value, write the value in the NULL position. 3) Add the leakage flow values in the SEAL column and write the result in the space for the SEAL total.
 4)  If the SEAL total leakage or the NULL total leakage (Flow No. Fig. 619 Step 4) is 4.0 GPM or more, replace the components with high leakage as necessary to decrease this leakage to less than 4.0 GPM.
Center Leakage Summary Sheet
 ~............................................................
 | Total Center System "Null" Leakage | [Flow No. Fig. 619 Step 4] | | Yaw Damper, Autopilot and Stab Trim | -----------------------------------| | | Yaw Damper Null Leakage | [Flow No.Fig. 618 Step 3] | | Lateral and Pitch Autopilot | Null Leakage [Flow No.Fig. 618 Step 7)]
| | Stab Trim Null Leakage | [Flow No. Fig. 618 Step 11] | | Spoiler Panels | --------------| | | | Spoiler Panel No. 1 | [Flow No. Fig. 619 | Step 22] | | Spoiler Panel No. 12 | [Flow No. Fig. 619 | Step 23] | | Ailerons | --------|
　
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