38A 38C 38B | Giant GP7122 guide

GP7122 REPAIR INSTRUCTIONS

CAUTION: Don't loosen the 3 plunger (36) before the valve casing has been removed otherwise the plunger (36) could hit against the spacer pipe (51F) when the pump is being turned.

14)Remove circlip ring (48) from seal sleeve (38). Re- move spacer disc (47) and seal ring (46) from seal sleeve. Replace worn or damaged parts.

38A

38C

38B

15)Remove leakage gasket (38B) from serrated pin (38A) on the seal sleave (38). Check o-ring (38C) for damage and replace if necessary. IMPORTANT! The 3.2 mm (diameter bore of the leak- age gasket (38B) must be inserted directly on the serated pin (38A) of the seal sleeve (38). The leakage gasket must fit snugly to the seal so that the bevelled surface of the gasket faces outwords.



45	44	43	42	43	42	41

16)Remove support disc (41) seal unit (42, 43, 44) and pressure ring (45) of seal sleeve (38). Examine seals for signs of wear or cavi- tation, and if necessary, replace.



36	33B	34	44

17)Examine plunger (36) for signs of wear or cavitation. If the surface of the plunger is worn, screw out the plunger with a 27mm tool. Clean centering and front surface of crosshead with plunger (25).Thread new plunger carefully through oiled seals in seal sleave. Coat thread of new plunger lightly with bonding agent (e.g., loctite).

NOTE: Seal life can be increased if the pretensioning allows for a little leakage. This assists lubrication and keeps the seals cool. It is therefore not necessary to replace seals before the leakage becomes too heavy and causes output and operating pressure to drop.