chevrolet truck Light Duty Truck 1994 Series, Руководство по ремонту

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5. Rear main bearing cap and bolts to the block.
• On 7.4L engines, apply anaerobic sealing com­
pound to the rear bearing cap sealing face or to
the rear bearing cap channel of the engine
block, from the corner of the rear thrust bearing
pocket to the edge of the channel as shown in
figure
68
. Do not allow any sealant on either
crankshaft or rear oil seal.
Q ,
Tighten
• Rear main bearing cap bolts temporarily to 4
N-m (35 lbs. in.).
t } | Measure (Figure 69)
Crankshaft end play, as follows:
A. Firmly thrust the crankshaft first rearward then
forward. This will line up the rear main bearing
and crankshaft thrust surfaces.
N O T IC E : R e f e r to “ N o t i c e ” o n p a g e 6 A 5 -1 .
Tighten
• Rear main bearing cap bolts to specifications:
— 5.0L and 5.7L engines: 110 N-m (80 lbs. ft.).
— 7.4L engines: 150 N-m (110 lbs. ft.).
B. With the crankshaft wedged forward, measure
at the front end of the rear main bearing with a
feeler gage (figure 69). The proper clearance is
0.0508-0.1524 mm (0.002-0.006-inch) (5.0L and
5 .7 L e n g in e s ) o r 0 . 0 5 0 8 - 0 . 2 5 4 0 m m
(0.002-0.010-inch) (7.4L engines).
C. On 5.0L and 5.7L engines, if correct end play
cannot be obtained, make sure the correct size
rear main bearing has been installed. Produc­
tion engines may have rear main bearings that
are 0.2032 mm (0.008 inch) wider across the
thrust faces than standard, as explained previ­
ously.
P Inspect
• Crankshaft for binding. Try turning the crankshaft to
check for binding. If the crankshaft does not turn
freely, loosen the main bearing cap bolts on one
cap at a time until the tight bearing is located.
Burrs on the bearing cap, foreign matter between
the insert and the block or the bearing cap, or a
faulty insert could cause a lack of clearance at the
bearing.
— A bent crankshaft could cause binding. Make
sure the steps outlined above have been per­
formed before suspecting a bent crankshaft.
CRANKSHAFT REAR O IL SEAL
INSTALLATION (7.4L ENGINES)
-►<- Install or Connect
Tool Required:
J 38841 Seal Installer
• Crankshaft rear oil seal.
A. Make sure the crankshaft rear chamfer is free
of grit, loose rust, and burrs. Correct as needed.
B. Lubricate the inner and outer diameter of the
seal with engine oil.
C. Install the seal on J 38841.
D. Position J 38841 against the crankshaft. Thread
the attaching screws into the tapped holes in
the crankshaft.
E. Tighten the screws securely with a screwdriver.
This will ensure the seal is installed squarely
over the crankshaft.
F. Turn the handle until it bottoms.
G. Remove J 38841.
CRANKSHAFT REAR O IL SEAL
AND RETAINER INSTALLATION
(5.0L AND 5.7L ENGINES)
■¥+
Install or Connect (Figures 70 and 71)
Tool Required:
J 35621 Seal Installer
• Whenever the seal retainer is removed, a new
retainer gasket and crankshaft rear oil seal must be
installed.
1
. Gasket (84) to the block. It is not necessary to use
sealant to hold the gasket in place.
2. Seal retainer (82).
N O T IC E : R e f e r to “N o t i c e ” o n p a g e 6 A 5 -1 .
3. Screws (80) and nuts (81).
Tighten
•S crew s (80) and nuts (81) to 15 N-m (11 lbs.
ft.).
4. Crankshaft rear oil seal (figure 71).
A. Make sure the crankshaft rear chamfer is free
of grit, loose rust, and burrs. Correct as needed.