Oilless Reciprocating Air Compressor Pumps
INSPECT PISTON AND PISTON RING (INSPECT EVERY 5,000 HOURS)
Figure 11
Figure 12
(B)
(A)
(C)
Figure 13
1.Remove cylinder head and cylinder.
2.Do not use tool to remove the ring.
NOTE: Expanding ring too much and deforming can cause wear and leakage. (See Figure 12). Mark upper surface (not lower surface) of removed ring for easy distinction.
3.Inspect lower surface (A) and outer side surface (B) of ring (See Figure 13). Measure thickness (C) of ring with calipers. Replace if foreign matter enters (A, B) or deep damage is found or (C) dimension is less than 2.5 mm at any point around the rings circumference.
NOTE: Clean the whole ring and ring groove with soft clean cloth.
| Ring and piston dust build up in the ring groove can | |
! CAUTION | ||
cause knocking. This is sometimes mistaken for bad valve |
or bearing.
REASSEMBLE: Pay attention to the fit of the piston and wrist pin fit. There should be no axial play or looseness in the wrist pin area.
NOTE: Do not separate piston from connecting rod when inspecting piston or ring. If you remove piston from connecting rod, you may damage oil seal of connecting rod and needle bearing.
PISTON REPLACEMENT
1.Inspect for appearance if there is deep damage or crack on top of piston or at pin boss.
2.Remove piston ring and inspect for breakage or droop of ring land.
3.Remove
4.Push piston pin to one side.
NOTE: Install bearing retention sleeve in grease kit/piston set. The retention sleeve is to prevent the needle bearing from falling out of the bearing area. On the HP cylinder only.
5. Remove piston pin.
Piston rings
Piston | Piston pin |
Figure 14
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