Mack E7, Руководство по обслуживанию

Страница: 178 / 303

Page 6-20
200 ENGINE ASSEMBLY
Due to the considerable weight of the
crankshaft, extreme care must be observed
during installation. No nicks, scratches,
burrs, or any other kinds of distress are
acceptable on the main bearing and/or
crankshaft journals and fillets.
6. Using a suitable lifting device, position the
crankshaft in the crankcase.
[212 HH] MAIN BEARING CAP
Unfinished main bearing caps are available for
servicing of E7 engines. These are undersize
bore bearing caps for service rebore:
앫
Cap, Intermediate and Front Main Bearing
(Semi-Finished), No. 223GB2131M
앫
Cap, Rear and Center Main Bearing
(Semi-Finished), No. 223GB2132
Special Tool Required
앫
Magnetic Base Indicator Tool J 7872
Installation
1. Clean bore in bearing cap and back of the
lower bearing inserts.
2. Install bearing insert in bearing cap bore.
The inserts must be installed dry.
The lower bearing inserts do not have a hole or a
notch. They are stamped with the word LOWER.
Do not mix caps or inserts. The caps are
numbered from 1 through 7, front to rear.
3. Lubricate threads of the bearing capscrews
with clean engine oil and place bearing
capscrews in the bearing cap holes.
4. Position cap in the correct location and start
the screws in the threads.
5. Using a plastic-faced mallet, tap bearing cap
down until it contacts the machined
mounting surface.
6. Tighten the screws until they contact the
bearing cap. At this time, tighten them only
to finger tight.
7. Repeat above steps for remaining main
bearing caps, except the center main
bearing cap. Torque bearing cap capscrews
to 210 lb-ft (285 N
폷
m) using torque wrench
J 24407 or equivalent.
Use standard thickness thrust washers initially.
Refer to Figure 6-21.
8. Place upper thrust washer sections in
position at the center bearing. The steel side
of the thrust washer goes toward the block,
the bronze side goes toward the crankshaft
(this applies to upper and lower thrust
washer sections).
Beginning with October 1996 production, new-
style thrust washers were introduced. These
thrust washers are steel backed with an
aluminum facing material on the side that goes
against the crankshaft. As with the previous
bronze-style thrust washers, the aluminum-faced
thrust washers have oil reservoir grooves cut into
the aluminum surface as well as tip face reliefs.
The aluminum thrust washers can easily be
installed incorrectly because of the similarity of
color between the steel backing and aluminum
face. When installing aluminum-faced thrust
washers, make sure the oil reservoir grooves and
tip relief cuts are facing against the crankshaft.
5-101.bk Page 20 Friday, March 17, 2006 11:05 AM