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Compressor History
Compressor History
The following describe changes made to the
X214, X418, X426, and X430 compressors.
Released
Four cylinder compressors with the gerotor oil
pump were released in 1983. Two cylinder
compressors with the gerotor oil pump were
released in 1993.
Two-piece Compressor Seal Plate
and Mounting Flange Assembly
In the third quarter 1988 the compressor seal
plate/mounting flange was changed to a two-piece
assembly on four cylinder compressors used in
trailer units.
Metal Bellows Crankshaft Seal with
Set Screws
In May of 1992 a new metal bellows crankshaft
seal with set screws was introduced for four
cylinder compressors.
Polyol Ester (POE) Compressor Oil
for HFC Refrigerants
In 1994 the use of Polyol Ester (POE) compressor
oil for HFC refrigerants was implemented.
Groove Top Pistons
In 1994 the pistons were changed from flat top to
groove top pistons. A groove top piston has small
concentric grooves on the top of the piston under
the ring valve. These grooves reduce the stiction
between the top of the piston and the ring valve.
Teflon Seal Type Drive End Ball
Bearing
In 1996 the drive end ball bearing was changed to
a Teflon seal type ball bearing.
New Coupling Mounting Washer
In the first quarter of 1998 the black coupling
washer was changed to a 0.23 in. thick silver
washer (P/N 77-2498).
Large Shaft Compressor
In August of 1998 the large shaft compressor was
introduced. The large shaft compressors,
(X426LS and X430LS) have a crankshaft drive
shaft diameter of 1.187 in. These compressors are
used in trailer units for improved reliability. The
large shaft compressors use a metric M12 X 1.75
coupling/clutch mounting bolt.
The original four cylinder compressors have a
crankshaft drive shaft diameter of 1.0 in. and are
often called small shaft compressors. They
typically use a 3/8-16 in. coupling/clutch
mounting bolt.
Metal Bellows Crankshaft Seal with
Drive Tangs
In August of 1998 a new metal bellows crankshaft
seal with drive tangs was introduced for use with
large shaft compressors.
8 Pin Coupling and Clutch
In the fourth quarter of 1998 the 6 pin coupling
and clutch were replaced with an 8 pin coupling
and clutch in trailer units.
Fins Eliminated from Crankcase
In 2002 the fins on crankcase castings were
eliminated.
Seven Quart Oil Sump on Four
Cylinder Compressors
In the first quarter of 2003 the seven quart oil
sump on four cylinder compressors used in
multi-temp trailer units was introduced.
Deep Oil Sump on Two Cylinder
Compressors
In the first quarter of 2003 the deep oil sump on
two cylinder compressors used in certain truck
units was introduced.