Chevrolet 40 60 Series Overhaul Manual Download

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5-12 POW ER BRAKE CYLINDER

Cleaning, Inspection and Repair

C le a n in g

General

Thoroughly wash all parts in a suitable cleaning fluid to

remove all traces of dirt, oil, or grease.

A ir Strainer

Thoroughly clean all air passages with a suitable cleaning

fluid to remove all traces of dirt, oil, or grease. Install new
polyurethane foam filter element into air strainers.

Cylinder Head

Soak cylinder head in cleaning fluid to loosen carbon from

discharge valve cavities and unloading cavity, and to loosen

rust and scale.  Blow dirt  out  of all cavities with compressed
air.  Scrape  carbon  and  dirt  from  all  surfaces.  Scrape  gasket
particles  from  gasket  surfaces.

Discharge Valves

Clean discharge valves, if not worn excessively or da

maged, by lapping with crocus cloth held on a flat surface.

Oil P assages

Thoroughly clean oil passages through crankshaft, con

necting  rods,  and  crankcase  rear  end  cover.  If  necessary,
prod  oil  passages  with  a  piece  of wire,  then  flush  passages
with  cleaning  fluid  and  blow  out  with  compressed  air.

Cylinder Block

Soak cylinder block in cleaning fluid to loosen carbon and

dirt  from  air  intake  cavity.  If water-cooled  type,  clean  rust
and  scale  from  water  passages.  Blow  out  all  passages  with
compressed  air.

Pistons

Scrape All Carbon and dirt out of ring grooves in pistons.

Clean drain holes in oil ring grooves.

Ball Bearing

Immerse bearing in cleaning fluid, then brush off old

lubricant.  Blow  bearing  dry  with  compressed  air,  and  wrap
in clean cloth.  Avoid spinning bearing with air blast, as spin
ning  might  damage  bearing.

Crankcase and Bottom Cover

On gear driven compressors, wash crankcase and bottom

cover in cleaning fluid. Remove all sediment from sump in

bottom of cover.

In sp e ctio n

Cylinder Head

Inspect cylinder head for cracks or breaks. Replace with

new head if cracked or damaged.

Inlet a nd Discharge Valve Sp rings

Discard used inlet and discharge valve springs and replace

with new springs.

Inlet a nd D ischarge Valves and Seats

Inspect inlet and discharge valves and seats for signs of

excessive wear. Replace valves if grooved deeper than 0.003"
at point of seat contact. Replace valve seats if condition is
such that seats can no longer be refaced.

Unloading Pistons and P lungers

Inspect pistons, plungers, and plunger guides for signs of

damage or excessive wear. New unloading pistons should
slide easily in bores. Replace "O" rings in unloader piston.

Crankcase and End Covers

Check crankcase and end covers for cracks or other dam

age. Replace with new parts if damaged.

Crankcase Bearing Bore

Check the fit of ball bearing in the compressor crankcase

bearing bore. The bearing should require a finger press fit.  It
is  recommended  to  replace  compressor  crankcase  if bore  is
worn  or  damaged.

Cylinder Block (Fig. 9G)

Use telescoping guage to check cylinder bores for out-of-

round and taper. Bores which are scored or out-of-round