
Service Instructions
137465E Rev. F May 2012
6
Section 2: Actuator Disassembly
Actuator Disassembly
2�2 Spring cylinder disassembly
NOTE: 
Review Section 2 steps 2.1.1 through 2.1.2 before proceeding with cylinder disassembly. 
 CAUTION: SPRINGS ARE PRELOADED
The spring in CBB Series Spring Return Actuators are preloaded.
 WARNING: POTENTIALLY DANGEROUS DISASSEMBLY
Actuator must be disassembled in the following manner.
2.2.1 Remove hex nut (1-80) as follows: CBB315 through 725 standard housing stop 
screw or extended stop (ES) use step 2.2.1.1. CBB315-SR-M3/M3HW through 
CBB725-SR-M3/M3HW use step 2.2.1.2.
2.2.1.1 For CBB315 through 725 housing stop screw or extended stop screw 
(ES): 
2.2.1.1.1 Loosen and remove hex nut (1-80) and washer (1-90) from stop 
screw (1-70) located in housing (1-10). 
2.2.1.1.2 Remove stop screw (1-70) located in housing (1-10). 
2.2.1.2 For CBB315/420/520/525/725-SR-M3 or M3HW: 
2.2.1.2.1 Remove retainer ring (12-30) and groove pin (12-20) from 
optional hex drive hub or from hand wheel (12-10). 
2.2.1.2.2  Remove optional hex drive hub or handwheel (12-10) from M3 
jackscrew (1-70). 
2.2.1.2.3 Loosen and remove hex nut (1-80) from M3 jackscrew (1-70). 
NOTE:
CBB420,520,525,725-SR-M3 or M3HW models: the M3 jackscrew (1-70) can not be removed now. 
The M3 jackscrew used in these models can be removed later in this procedure per step 2.3.7. 
2.2.2 Loosen and remove hex nut (4-40) and washer (4-90) from end cap stop screw  
(4-30) or from end cap extended stop (4-30).
NOTE: 
Extended stop or end cap stop screw (4-30) does not require removal from end cap (4-20)      
unless replacing with a new extended stop or stop screw.
2.2.3 Remove breather (30) from end cap (4-20).
2.2.4 Remove acorn nut (8-20) and gasket seal (5-50) from end cap (4-20).
2.2.5 Use a ratchet and socket on the welded nut, located on the housing end of center bar 
assembly (8-10), rotate center bar assembly (8-10) counter-clockwise (CCW). This 
will cause end cap (4-20) to gradually unscrew from center bar assembly (8-10).