Bendix Commercial Vehicle Systems TU-FLO 600 AIR COMPRESSOR 9/04 User Manual
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CRANKSHAFT
Check crankshaft screw threads, keyways, tapered ends
and all machined and ground surfaces for wear, scores, or
damage. Crankshaft journals which are out of round more
than .001 in. (.025 mm) must be reground. Bearing inserts
are available in .010 in. (.254 mm), .020 in. (.508 mm), and
.030 in. (.762 mm) undersizes for reground crankshafts.
Main bearing journals must be maintained so bearings are
snug fit. The oil seal ring groove or grooves in crankshafts
fitted with oil seal rings must not be worn. The ring groove
walls must have a good finish and they must be square.
Check to be sure the oil passages are open and clean
through the crankshaft.
CONNECTING ROD BEARINGS
Check connecting rod bearings on crankshaft journals for
proper fit. Used bearing inserts should be replaced.
Connecting rod caps are not interchangeable. The locking
slots of the connecting rod and cap should be positioned
adjacent to each other.
Clearance between the connecting rod journal and the
connecting rod bearing must not be less than .0003 in. (.008
mm) or more than .0021 in. (.053 mm) after rebuilding.
MAIN BEARINGS
Check for wear or flat spots; if found, bearings should be
replaced. If type with sleeve bearing, this bearing should
be checked for scores and wear and replaced if necessary.
UNLOADER MECHANISM
Used unloader mechanism should be replaced by unloader
kits (piece number 279615).
The new unloader pistons should be a loose sliding fit in the
unloader piston bores of the cylinder block.
REPAIRS
DISCHARGE VALVES AND SEATS
If discharge valve seats merely show signs of slight wear,
they can be dressed by using a lapping stone, grinding
compound and grinding tool. Install new valve springs and
re-dressed or new discharge valves.
To test for leakage past the discharge valves, apply about
100 pounds of air pressure through the cylinder head
discharge port and apply soap suds at the discharge valves
and seats. Leakage which will permit the formation of bubbles
is permissible.
If excessive leakage is found, leave the air pressure applied,
and with the use of a fibre or hardwood dowel and hammer,
tap the discharge valves off their seats several times. This
will help the valves to seat and should reduce any leakage.
With the air pressure still applied at the discharge port of
the cylinder head, check for leakage at the discharge valve
cap nuts. No leakage is permissible.
INLET VALVES AND SEATS
If inlet valve seats show sign of slight nicks or scratches,
they can be redressed with a fine piece of emery cloth or
by lapping with a lapping stone, grinding compound and
grinding tool. If the seats are excessively damaged to the
extent that they cannot be reclaimed, they should be
replaced. The dimension from the top of the cylinder block
to the inlet valve seat should not exceed .113 in. (2.870 mm)
not be less than .101 in. (2.565 mm).
Slightly worn or scratched inlet valves can be reclaimed by
lapping them on a piece of fine crocus cloth on a flat surface,
but it is suggested that new inlet valves be installed.
ASSEMBLY
INSTALLING CYLINDER BLOCK
Position cylinder block gasket and block on crankcase
according to markings made prior to disassembly. Using
cap screws with lockwashers, secure cylinder block to
crankcase at 220 to 250 inch pounds.
INSTALLING CRANKSHAFT
If the crankshaft is fitted with oil seal rings, install rings.
Position ball bearings and crankshaft in crankcase making
sure the drive end of the crankshaft is positioned as marked
before disassembly.
If one end of the crankcase is counterbored for holding a
bearing, be sure the crankshaft is installed through the
correct end of the crankcase.
Carefully press crankshaft and bearings into crankcase
using arbor press.
FIGURE 18 - PISTON RING POSITIONS GAPS & GROOVE
CLEARANCE
TU-FLO
®
500 & 600 AIR COMPRESSOR
CORRECT GROOVE
CLEARANCE
NARROW
RING
WIDE RING
.0035”
.0015”
.002”
.004”
CORRECT GAP
CLEARANCE WITH
RING IN CYLINDER
.0035
.015
WIDE
NARROW
WIDE
NARROW
INCHES
M M
.038
.0015
.051
.002
.089
.0035
.102
.004
.381
.015