Chevrolet 1977 light duty truck, Руководство по обслуживанию

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loose in cylinder heads should be replaced with new
studs available in .003" and .013" oversize. Studs may be
installed after re a m in g the holes as follows:
1. Remove old stud by placing Tool J-5802-1 over
the stud, installing nut and flat w asher and rem oving
stud by turn in g nut (fig. 6A-33V).
2. R eam hole for oversize stud using Tool J-5715
for .003" oversize or Tool J-6036 for .013" oversize (fig.
6A-34V).
CAUTION: Do not attem pt to install an
oversize stu d without ream ing stud hole.
3. C oat press-fit area o f stud with hypoid axle
Fig. 6A 33V--Removing Rocker Arm Stud (Sm all V8)
Fig. 6 A -3 5 V -In s ta llin g Rocker Arm Stud (Sm all V8)
lubricant. Install new stud, using Tool J-6880 as a guide.
G au g e should bottom on head (fig. 6A-35V).
VALVE G U ID E BORES
Valves with oversize stems are available (see
specifications). To ream the valve guide bores for
oversize valves use Tool Set J-5830 for Small V8 or
J-7049 for M ark IV V8.
VALVE SEATS
R econditioning the valve seats is very im portant,
because the seating o f the valves must be perfect for the
engine to deliver the power and pe rfo rm a n c e built into
it.
A nother im p o rtan t factor is the cooling o f the valve
heads. Good contact between each valve and its seat in
the head is im perative to insure th at the heat in the valve
head will be properly carried away.
Several different types o f eq u ip m en t are available
for reseating valves seats. The recom m endations o f the
m a n u factu rer o f the equipm ent being used should be
carefully followed to attain proper results.
Regardless o f w h at type o f eq u ip m en t is used,
however, it is essential that valve guide bores be free
from carbon or dirt to ensure proper centering o f pilot
in the guide.
Reconditioning
1. Install e xpanding pilot in the valve guide bore
and expand pilot.
2. Place ro ughing stone or fo rm ing stone over pilot
a n d ju st clean up the valve seat. Use a stone cut to
specifications.
3. Remove roughing stone or fo rm ing stone from
pilot, place finishing stone, cut to specifications, over
pilot and cut just enough metal from the seat to provide
a smooth finish. Refer to specifications.
4. Narrow down the valve seat to the specified width.
5802
OVERSIZE