(a)  
Put the speed brake lever in the down and locked (DN) position.

 (b)  
Measure and make a record of the tension in the SBB cable.

 (c)  
Measure and make a record of the tension in the SBA cable.

 (d)  
Subtract the tension value of the SBA cable from the tension value of the SBB cable.

 (e)  
Make a record of the difference between the two cable tensions.

 (f)  
Make sure the difference is between 25 to 35 pounds (11-15kg).

 (g)  
If the difference is not 25 to 35 pounds(11-15kg), adjust the forward control rod (Fig. 501): 1) Move the speed brake lever out of the DN detent position

 while you adjust the forward control rod. 2) If the difference is less than 25 pounds(11kg), increase the length of the forward control rod.
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 3) If the difference is more than 35 pounds (15kg), decrease
 the length of the forward control rod. 4) Move the speed brake lever back to the DN position. 5) Measure the cable tensions of the SBA and SBB cables. 6) Make sure the difference between the cable tensions is
 approximately 30 pounds (14kg). 7) Adjust the forward control rod again if it is necessary.
 S 825-026
 (11)
 Adjust the downstop (Section B-B, Fig. 501):

 (a)  
Move the speed brake lever to the DN position.

 (b)  
Adjust the downstop until there is a clearance of 0.030 to

 0.050 inch (.76 to 1.27mm) between the downstop and the locking arm shoe.
 NOTE:____Do not push the locking arm shoe. This can move the shoe and change the gap.
 S 825-027
 (12)
 Adjust the cam follower (Fig. 503):

 (a)  
Move the speed brake lever to the DN position.

 (b)  
If you will use the bushing G27018-3 or MIT61B04016-86 Part 2, install the bushing on the cam roller. 1) Make sure the bushing is within 0.010 inch (.25mm) of the

 cam lobe.

 (c)  
If you will not use the bushing G27018-3 or MIT61B04016-86 Part 2, measure the clearance between the cam roller and the cam lobe (Detail A).

 (d)  
If the clearance is not in the tolerance, add or remove the laminations of the shim below the support bracket.

 (e)  
If it is necessary, remove the bushing.

 S 825-028
 (13)
 Adjust the arm switch (Fig. 503):

 (a)  
Make sure the following circuit breaker is open and a DO-NOT-CLOSE tag is installed: 1) P7, Overhead Circuit Breaker Panel

 a) 7G6, SPEED BRAKE AUTO CONT
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 (b)  
Move the No. 1 and No. 3, thrust levers to the idle position.

 (c)  
Move the No. 2 and No. 4 reverse thrust levers to the idle position.

 (d)  
Move the speed brake lever to the UP position and to the DN position.

 (e)  
Connect an ohmmeter or a continuity test light across pin 3 and pin 4, on the terminal block, T215.

 (f)  
Cut the lockwire and loosen the mounting nuts on the switch.

 (g)  
If you will use the bushing G27018-4 or MIT61B04016-86, Part 3, adjust the arm switch: 1) Install the bushing on the cam roller. 2) Move the speed brake lever until the bushing touches the

 lobe on the cam.
 3) Adjust the arm switch forward against the striker plate
 until there is no continuity between pins 3 and 4.
 4) Slowly adjust the arm switch aft (away from the striker

 plate) until there is continuity between pins 3 and 4. 5) Remove the bushing from the cam roller.
 (h)  
If you will not use the bushing G27018-4 or MIT61B04016-86 Part 3, adjust the arm switch: 1) Adjust the arm switch forward against the striker plate
　
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