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4.7.3 Disassembly - Cross-Head Cylinder/Piston
1. Decompress and degas the compressor.
2. Remove low pressure compression cylinder assembly (ref.section 4.8) and /
or high pressure cylinder assembly (refer section.4.9) as per procedures
detailed in this section.
3. Remove oil filler bowl (CRA-820 section 4.3) assembly from top of
crankcase.
4. Remove big end cap from Connecting Rod.
5. Remove cross head piston assembly complete with Conrod.
6. Remove gudgeon pin end plate (RO-2535) retaining bolt (BNF-0644).
7. Slide Gudgeon pin out of piston and Conrod. Take note of top of Conrod
and top of crosshead piston. (Conrod serial # is always facing the top)
8. If removing both high pressure throw and low pressure throw crosshead
pistons, take note of which crosshead belongs to high pressure throw and
which belongs to low pressure throw. When reassembling, they cannot be
mixed up.
9. Check condition of big-end bearing shells.
10. Remove cross head cylinder from crankcase.
11. Check the condition of the bore, i.e. check for score marks and measure
inside diameter.
4.7.4 Assembly - Cross-Head Cylinder/Piston
Instructions
Cautionary Notes
1. All components to be cleaned and oiled
before assembly
Check for damage
2. Fit o-ring (ORN-7262) into corner of
cross head cylinder
Lightly grease o-ring
3. Slide cross head cylinder over studs.
Orientate so that the radiused cut out on
cross head skirt is adjacent to crankshaft
counterweight.
4. Tighten nuts to correct torque. See Torque
Setting Chart (section 3.4.4))
Check clearance of crankshaft
counterweight on skirt of cylinder.
5. Position the con-rod (ROA-8525) inside
the cross head piston (con-rod serial # to
the top). Align gudgeon pin holes and fit
gudgeon pin.
Ensure that high pressure side cross head
piston is fitted to high pressure throw and
low pressure side cross head piston is
fitted to low pressure throw.
NOTE: Both, the top of the crosshead
piston and the bottom of the cross head
piston have oil retention grooves. In 1
Intermech Ltd. BBR-6015-2 Compressor Service Manual
