Instruction Manual

6.8 SWIVEL AIR INLET (74200-12700)
• Using an Allen key* remove screw 40 and washer 39.
• Remove swiveling inlet 38.
• Unscrew double male connector 41 from swiveling inlet 38 and remove nylon washer 33.
• Using a spanner*, remove drilled bolt 37.
• Remove two nylon washers 33 and air inlet block 35.
• Remove circlip 97 from double male connector 41 using circlip pliers and withdraw sintered lter 96.
• Assemble in reverse order of dismantling.
• Refers to items included in the 74200 service kit. For complete list see page 13.
Item numbers in bold refer to the General Assembly drawing and parts list (pages 18-19).
6.9 DIFFERENTIAL VALVE
• Using special at spanner* unscrew valve locking plug 27, withdraw and remove spring 104 and ‘O’ ring 29.
• Remove silencer 34 using a spanner* and remove nylon washer 33.
• Push valve piston 28 out from its housing together with ‘O’ rings 30, 31&32.
• Check spring 104 for distortion and renew if required.
• Assemble in reverse order of dismantling.
6.10 HEAD ASSEMBLY
• Remove nose equipment prior to commencing dismantling.
• Using spanners* remove spindle 44 and locknut 45.
• Remove return spring locknut 46 using a spanner*.
• Remove return spring 47, washer 99 and locking ring 90.
• Check return spring 47 for distortion and renew if required.
• Assemble in reverse order of dismantling.
6.11 REAR CASING
• Using an Allen key* remove screw 40 from stroke set nger 88 and lift o bridge washer 95.
• Disengage stroke set nger 88 by pushing it back against spring 89.
• Unscrew rear casing 86.
• Remove rear casing rubber band 87 if necessary.
• Extract circlip 84 using circlip pliers* and remove sintered silencer 85.
• Complete assembly in reverse order of dismantling. Locate pawl 102 in head before screwing on rear casing 86.
6.12 DISTRIBUTOR
* Using an Allen key* remove two screws 40.
* Withdraw distributor 83 together with air motor end plug 81 and ‘O’ rings 82&31 taking care not to drop ball 79 and
push rod 78.
* Using an Allen key* remove four countersunk socket head screws 58 and withdraw stroke stop 57.
* Pull out two air supply tubes 59 and four ‘O’ rings 60.
* Assemble in reverse order of dismantling.
6.13 HYDRAULIC PISTON & AIR MOTOR ASSEMBLY (74200-12610)
• Wrap adhesive tape around hydraulic piston 54 thread and move assembly backwards slowly and rmly. Using circlip
pliers* remove circlip 52 and front seal 51.
• Remove ‘O’ rings 76 and 77.
• Using two spanners* separate the hydraulic piston 54 from air motor casing 75. Shim adjustment ring 55, movement
pivot 56 and ‘O ring 101 will come out with hydraulic piston 54.
• Remove air motor assembly out of air motor casing 75, remove circlip 61 using circlip pliers*, then tap air motor casing
75 on bench to free components.
* Refers to items included in the 74200 service kit. For complete list see page 13.
Item numbers in bold refer to the General Assembly drawing and parts list (pages 18-19).
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ORIGINAL INSTRUCTION ENGLISH