TM 5-6115-400-35
(8) Shaft Radial Movement.
Permissible
(b) Thrust Spacer. Check the thrust
radial movement of the turbine impeller
spacer for indications of scoring and
shaft is .005 inch to .008 inch. Radial
excessive wear. Surfaces of the
movement in excess of .008 inch
sealing ring groove must be smooth
indicates wear of shaft journals and I.D.'s
and the walls must be parallel.
of shaft bearings, shaft bearing O.D.'s and
Width of groove must not exceed
I.D.'s of center housing bearing bores.
.0715 inch.
Refer to the shaft radial movement
(c) Thrust Ring. Make certain that all
readings made during the 2,000 hour
thrust ring (20, fig. 32) oil passages
service inspection.
Disassemble and
are open and clean and that thrust
replace either the impeller shaft bearings,
faces of the ring are not scored or
center housing, or rotating shaft assembly
warped. Measure overall thickness
to establish the specified radial movement
of the ring with a micrometer at
of .005 inch to .008 inch.
three points, 1200 apart. Readings
g. Turbocharger Reassembly.
The workbench
must not be less than .299 inch nor
area and tools must be kept clean at all times during
vary more than .001 inch between
turbocharger assembly operations to preclude the
measurements.
entrance of foreign material.
All parts must be
(d) Turbine Impeller and Shaft. Check
absolutely clean and free of nicks/burrs before they are
impeller for signs of wear. Check
installed in the turbocharger.
surfaces of impeller vanes for
(1) Install the center housing oil reservoir
cracks and check edges of valve for
plug if it was removed during cleaning
indications of erosion. The shaft
operations.
must not show signs of scoring,
scratches of bearing seizure.
(2) Install the two internal snap rings. To
Measure shaft journals with a
install snap rings use snap ring pliers.
micrometer. Journals must not be
out of round and' diameter must not
Caution.
be less than .6245 inch.
Use care to avoid scratching the
(7) Turbine Impeller Shaft End Play. Shaft
center housing bore.
end play is predetermined by the finished
machined parts that comprise the center
(3) Lubricate and install bearing in turbine
housing and rotating parts. No shim pack
end of housing. Install outside snap ring
is required to adjust end play before final
using snap ring pliers.
assembly. If shaft end play exceeds .008
(4) Clamp holding fixture, Tool A, in a vise.
inch, excessive wear has taken place on
Lubricate turbine impeller shaft journals.
one or both thrust surfaces of the thrust
Insert hexagon countersunk hole in
ring, the bearing surface of the center
turbine wheel over hexagon stud in the
housing thrust plate assembly, or the
holding fixture. With turbine end of center
thrust bearing. Shaft end play measuring
housing facing downward, guide housing
less than .003 inch indicates that foreign
onto shaft.
Do not scuff or scratch
material has accumulated between the
bearing surfaces.
impeller and center housing, or between
the thrust ring faces and bearing surfaces
in the center housing. Clean/replace all
parts necessary to establish the specified
end play of .003 inch to .008 inch.
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