[212 Cb] Auxiliary Driveshaft Bushing Replacement - Mack E7 Service Manual

5-101.bk Page 9 Friday, March 17, 2006 11:05 AM
[212 CB] Auxiliary Driveshaft
Bushing Replacement
DESCRIPTION
The front and rear auxiliary driveshaft bushings
are identical. Engine lubrication oil passing
through the No. 1 camshaft bushing supplies oil
to the front auxiliary driveshaft bushing. Oil
passing through the No. 4 camshaft bushing
supplies oil to the rear auxiliary driveshaft
bushing. A groove in the rear auxiliary driveshaft
journal, in conjunction with a rifle-drilled hole in
the auxiliary driveshaft and a small oil feed tube,
supplies lubrication to the air compressor.
INSPECTION
1. Using a telescope gauge or inside
micrometer, measure the auxiliary bushing
bores. Take two readings, perpendicular to
each other, in each bore. Record the
readings. Refer to Figure 6-10.
2. Compare readings with the tolerances listed
in the Fits and Limits chart in this manual.
Figure 6-10 — Auxiliary Driveshaft Bushing ID Check
200 ENGINE ASSEMBLY
INSTALLATION
Correct installation of auxiliary driveshaft
bushings is very important. If bushings are
misaligned, lubrication oil will not be allowed to
lubricate the auxiliary driveshaft journal. This will
also cause the component lubricated through that
journal to run without lubrication and prematurely
fail.
If the approximately 1.25 inches long (32 mm) oil
feed tube, which connects the oil feed hole in the
rear of the auxiliary shaft to the oil feed hole in the
front of the air compressor crankshaft, is
accidentally lost during air compressor or
auxiliary shaft service work, the compressor will
fail from oil starvation. Also, the loss of oil
pressure resulting from the missing tube can
cause damage and problems in other
components and parts.
Refer to Figure 6-11.
1. Position a replacement bushing (2) against
2. Using a dark-colored felt-tip marker, mark
3. Clean the surfaces of the bushing and the
4. Using camshaft bushing remover/installer kit
the side of the block at the rear bushing
bore. Align the oil hole in the bushing with
the hole in the block.
the block and the bushing with a line (1) to
facilitate correct alignment during
installation.
bore. Dry both surfaces with compressed
air.
J 21428-01 (4) and the appropriate pilot
adapter J 37713 (3), install the bushing.
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