Carrier 69NT40-541-505, Руководство по эксплуатации и обслуживанию, Страница: 101 / 143

7–9 T-368
7.8.4 Preparation
a. Suction and Discharge Valves
If the valve seats look damaged or worn, replace valve
plate assembly. Always use new valves because it is
difficult to reinstall used valves so that they will seat as
before removal. Any valve wear will cause leakage.
Figure 7.13 Suction Valve and Positioning Rings
1. Suction Valve
2. Suction Valve Positioning Spring
3. Valve Plate Dowel Pin
- - - - -
Suction valves are positioned by dowel pins (see Fig-
ure 7.13 ). Do not omit the suction valve positioning
springs. Place the springs so that the ends bear
against the cylinder deck (middle bowed away from cyl-
inder deck). Use new gaskets when reinstalling valve
plates and cylinder heads.
b. Compression Rings
The compression ring is chamfered on the inside cir-
cumference. This ring is installed with the chamfer
toward the top. Stagger the ring end gaps so they are
not aligned.
Figure 7.14 Piston Ring
The gap between the ends of the piston rings can be
checked with a feeler gauge by inserting the ring into
the piston bore approximately one inch below the top of
the bore. Square the ring in the bore by pushing it
slightly with a piston. The maximum and minimum
allowable ring gaps are 0.33 and 0.127mm (0.013 and
0.005 inch) respectively.
7.8.5 Installing the Components
a. Push pistons from the inside of the crankcase
through the cylinders, be careful not to break
rings. Place rods so that the chamfered side is
against radius of crankpins. Install the crank-
shaft and thrust washer through the pump end
of the compressor. Ensure thrust washer is fitted
on locating pin. Do not damage main bearings.
Bring rods in position against crank bearings.
b. Install the pump end thrust washer on the two
dowel pins located on the bearing head (see
Figure 7.8 ).
CAUTION
!
Ensure that the thrust washer does not fall
off dowel pins while installing oil pump.
CAUTION
!
The set screw on the crankshaft must be
removed for this type of oil pump (see
Figure 7.8 ).
c. Install bearing head assembly with a new gasket
on the compressor crankshaft. Carefully push oil
pump on by hand, ensuring the thrust washer
remains on the dowel pins. The tang on the end
of the drive engages the slot in the crankshaft,
and the oil inlet port on the pump is aligned with
the oil pickup tube in the crankcase. The pump
should be mounted flush with the crankcase,
and oriented with the oil pick up tube and oil
inlet port, and aligned as shown in Figure 7.8 .
d. Align gasket and install eight cap screws in mount-
ing flange. Refer to Table 7–5 for torque values.
e. Install matching connecting rod caps Be sure
rod is not bound and crankshaft will turn cor-
rectly as each set of rod bolts is torqued.
f. Be sure key fits properly when installing rotor on
shaft. Screw on equalizer tube and lock screw
assembly with lock washer and bend over tabs
of lock washer. Assemble suction strainer to
motor and cover, and bolt cover to crankcase.
Assemble valve plates and gaskets. Assemble
cylinder heads & gaskets. Turn shaft by hand to
see that it moves freely.
g. Install the oil suction screen, the oil suction
screen hold down plate, and the bottom plate.
7.8.6 Compressor Oil Level
CAUTION
!
Use only Carrier Transicold approved
Polyol Ester Oil (POE) − Castrol-Icematic
SW20 compressor oil with R-134a. Buy in
quantities of one quart or smaller. When
using this hygroscopic oil, immediately
reseal. Do not leave container of oil open
or contamination will occur.
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