Service Procedure; Head Cylinder Subassembly; Handle Subassembly; Air Valve Subassembly - Cherry CHERRYMAX G746A Original Instructions Manual

TM-G746A Rev.: B DCR# 17-0231
Tools Needed:
700B65 (Packing Plug Wrench), 700A61 (Piston Rod Wrench), 700A62 (Power Cylinder Tool), 700A60 (Seal Guide), 9/64" Hex
Key, A Bent Hook
Disassembly Instructions:
• Remove the Pulling Head (if any installed) then remove the Head Cylinder (1) by unthreading the four Cap Screws (19)
HEAD SUBASSEMBLY
Tools Needed:
701A67 (Seal Guide), 1-3/8 Standard Wrench, 1/8" and 9/64" Hex Keys
Disassembly Instructions:
• Remove back cap (12) and push the head piston (7) out carefully.
• O-rings (5, 8) and Back-up Ring (6) can be removed and replaced using a bent hook.
Re-assembly Instructions – Use the 701A67 Guide over the Piston threads to protect the seals.
• Replace all O-Rings and Backup rings then re-assemble by reversing the directions given above.
POWER HANDLE SUBASSEMBLY
Tools Needed:
700B65 (Packing Plug Wrench), 700A61 (Piston Rod Wrench), 700A62 (Power Cylinder Tool), 700A60 (Seal Guide), 9/64" Hex
Key, A Bent Hook
Disassembly Instructions:
• Remove the Head Cylinder (1) and set it aside
• Drain all the fluid, then turn up-side down and remove the bottom covers (39 through 43);
• Push the power piston all the way down and unthread the locknut (38) and then remove the air piston (37) by using wrench
700B65; hold the top of the piston with tool 700A61 to prevent it from turning. Push piston out when completely unthreaded
• Remove packing plug (34) with the help of wrench 700B65.
• Tap the power cylinder (26) from the top (use tool 700A62); when loosened, it will fall through the bottom of the handle.
• Remove all the seals and inspect all components for wear. Replace all seals and worn components
Assembly Instructions:
• The re-assembly sequence is the opposite of disassembly; to prevent damage to piston threads; suggested tightening torque
for the locknut (38) between 51 and 59 in.-lb. (5.65 and 6.67 N-m).
• After service, the riveter must be primed and bled (page 15)

AIR VALVE SUBASSEMBLY

Tools Needed:
P1178 (Valve Extractor), 836B700 (Spring Installation Tool), 837B700 (Valve Sleeve Removal Tool), Needle Nose Pliers
Disassembly Instructions:
• Remove retaining ring (55) and muffler (54).
• Pull out the valve plug (53) and the Valve Spool (48) with the help of extractor P1178;
• Dislodge and pull the spring (46) out using needle-nose pliers
• In the unlikely event that you want to pull the Valve Sleeve (45), use the tool 837B700 (internal expansion collet).
Assembly Instructions:
• Replace all O-Rings and apply an O-ring lubricant (Parker® silicone lube or equivalent).
• To re-assemble, reverse the procedure given above; snap the Spring (46) into its groove with the help of tool 836B700
• Make sure that all retaining rings are properly seated in their grooves. (41) and (55).
DATE: 3/21/17 Federal Identification Code: 11815

SERVICE PROCEDURE

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