Specifications

6
FIGURE 10 - MEASURING CYLINDER BORES
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.)
Straighten the prongs of the connecting rod bolt lock strap
and remove the bolts and bearing caps. Push the piston
with the connecting rods attached out the top of the cylinders
of the crankcase. Replace the bearing caps on their
respective connecting rods. Remove the piston rings from
the pistons. If the pistons are to be removed from the
connecting rods, remove the wrist pin lock wires or teflon
plugs and press the wrist pins from the pistons and
connecting rods.
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. (See inspection of Parts) Discard the
piston rings and the connecting rod journal bearings.
Discard the wrist pin bushings if they were removed.
Crankcase
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.)
Remove the four cap screws securing front or drive-end
end cover or flange adapter. Remove the end cover, taking
care not to damage the crankshaft oil seal or front main
bearing, if any. Remove both of the small seal rings from
the crankcase, and the O-Ring from around the front end
cover. 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. Remove both of the
small seal rings from the crankcase and the O-Ring from
around the end cover. 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
Remove the unloader spring, spring saddle, and spring seat
from the inlet cavity of the crankcase, using long nose pliers.
Remove the unloader plungers and guides. 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.
CLEANING OF PARTS
General
All parts should be cleaned in a good commercial grade
solvent and dried prior to inspection.
Cylinder Head
Remove all the carbon deposits from the discharge cavities
and all the rust and scale from the cooling cavities of the
cylinder head body. Scrape all the foreign matter from the
body surfaces and use shop air pressure to blow the dirt
particles from all the cavities.
Crankcase
Clean the carbon and dirt from the inlet and unloader
passages. Use shop air pressure to blow the carbon and
dirt deposits from the unloader passages.
Oil Passages
Thoroughly clean all oil passages through the crankshaft,
crankcase, end covers, and base plate or base adapter.
Inspect the passages with a wire to be sure. Blow the
loosened foreign matter out with air pressure.
INSPECTION OF PARTS
Cylinder Head Body
Inspect the cylinder head for cracks or damage. Apply
shop air pressure to one of the coolant ports with all others
plugged, and check for leakage by applying a soap solution
to the exterior of the body. If leakage is detected, replace
the head.
End Covers
Check for cracks and external damage. If the crankshaft
main bearings are installed in the end cover, check for
excessive wear and flat spots and replace them if necessary.
If the compressor has an oil seal in the end cover, it should
be removed by pressing it out of the end cover.
Crankcase
Check all crankcase surfaces for cracks and damage. On
compressors where ball bearing main bearings are used
the difference between the O.D. of the outer race and the
I.D. of the crankcase hole should be .0000 in. to .0015 in.
loose. This is to maintain the correct press fit. The crankcase
must be replaced if the fit is too loose.