Bendix Tu-Flo 550 Air Compressor Disassembly; Governor; Cylinder Head - GMC C Series 1993 Repair Manual

5J-2 AIR COMPRESSOR ANO GOVERNOR

BENDIX TU-FLO 550 AIR COMPRESSOR DISASSEMBLY

Remove road dirt and grease from the compressor
with a cleaning solvent. Before disassembling the com­
pressor, mark the following items to show their relation­
ship when the cdmpressor is assembled (figure 2):
• Rear cover in relation to the crankcase.
• Base plate or adapter in relation to the crankcase:
• Cylinder head in relation to the crankcase.

GOVERNOR

« ■ + Remove or Disconnect
1. Bolts.
2. Washers.
3. Governor.
4. Gasket.

CYLINDER HEAD

+1 Remove or Disconnect (Figure 3)
Tools required:
J 25447-A Valve Remover and Installer
1. Cylinder head bolts (1).
2. Cylinder head (20).
* Tap the head with a soft faced mallet to break
the gasket seal.
3. Unloader cover plate bolts (2) and washers (3).
4; Unloader cover plate (4) and gasket (5).
Clean
• Gasket material from the cover plate, cylinder
head, and crankcase.
5. Unloaders (7), O-rings (6), and springs (8).
I? Inspect
• Unloader piston bushings (9) for nicks, wear*
corrosion, and scoring.
Figure 1—Compressor Identification
• If the unloader bushing is damaged or worn
^excessively, replace the cylinder head or com­
pressor.
Measure
m
i| Discharge valve travel before disassembling the
discharge valve mechanism.
A.
;; B;; Record the travel from closed to completely
: open.
iiiCi lf the measured travel exceeds 0.046
inches, replace the cylinder head or com­
pressor.
D. If the measured travel does not exceed
0.046 inches, continue with disassembly,
6. Discharge valve seats (16) using a 9/16 inch hex
socket!
7. PtScharge valves (17).
8. Discharge valve springs (18).
JV inspect
Discharge valve components for nicks, cracks,
>
and excessive wear.
— If wear is excessive, replace the affected
parts.
— If wear is minor, refer to "Repairs."
Figure 2—Marking the Compressor Components
Set up a dial indicator as shown in figure 4.