TM 5-3810-300-24 & P2
2. Crankcase Base Plate or Adapter.
A. Remove the cap screws securing the base plate or base adpater. Tap with soft mallet to break the gasket
seal.
B. Scrape off any gasket material from crankcase and plate or adapter.
3. Connecting Rod Assemblies.
NOTE
BEFORE REMOVING THE CONNECTING RODS, MARK EACH CONNECTING ROD AND ITS CAP.
EACH CONNECTING ROD IS MATCHED TO ITS OWN CAP FOR PROPER BEARING FIT, AND
THESE PARTS MUST NOT BE INTERCHANGED.
A.
Straighten the prongs of the connecting rod bolt lock strap and remove the bolts and bearing caps.
B.
Push the piston with the connecting rods attached out the top of the cylinders of the crankcase.
C.
Replace the bearing caps on their respective connecting rods.
D.
Remove the piston rings from the pistons. If the pistons are to be removed from the connecting rods,
remove the wrist pin lock wires and press the wrist pins from the pistons and connecting rods.
E. If the pistons are removed from the rod, inspect the bronze wrist pin bushing. Press out and replace the
bushing if it is excessively worn.
F. Discard the piston rings and the connecting rod journal bearings. Discard the wrist pin bushings if they were
removed.
4. Crankcase.
A. Remove the key or keys from the crankshaft and any burrs from the crankshaft where the key or keys were
removed.
NOTE
THROUGH DRIVE COMPRESSORS MAY HAVE A CRANKSHAFT KEY AT BOTH ENDS.
B.
Remove the four cap screws securing front or drive-end end cover or flange adapter.
C.
Remove the end cover, taking care not to damage the crankshaft oil seal or front main bearing, if any.
D.
Remove both of the small seal rings from the crankcase, and the O-Ring from around the front end cover.
E.
Remove the four cap screws securing the rear end cover and remove the rear end cover taking care not to
damage the rear main bearing, if any.
F.
Remove both of the small seal rings from the crankcase and the O-Ring from around the end cover.
G.
If the compressor has ball type main bearings, press the crankshaft and ball bearings from the crankcase,
then press the ball bearings from the crankshaft.
H.
Remove the unloader spring, spring saddle, and spring seat from the inlet cavity of the crankcase, using
long nose pliers.
I.
Remove the unloader plungers and guides.
J.
Cover the inlet cavity with a shop rag and apply air pressure to the governor mounting pad unloader port to
blow the unloader pistons out of their bores and into the inlet cavity.
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