Honda Acura NSX 1991, Руководство по обслуживанию

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Valve Guides
. Replacement
1 . As illustrated, in the removal steps of this procedure
use a commercially-available air-impact driver at-
tachment which may need to be modified to fit the
diameter of the valve guides. In most cases, the
same procedure can be done using Valve Guide
Drivers and a conventional hammer. Tool numbers
are at the end of this procedure.
VALVE GUIDE DRIVER
5 . 3
m m
(0.21
in)
2.
3.
87
mm-
- l -
57
mm
(3.43
in.)
(2.24
in.)
1 0 . 8
m m
(0.42
in)
Select the proper replacement guides and chill them
in the freezer section of a refrigerator for about an
hour.
Use a hot plate or oven to evenly heat the cylinder
head to 1
Monitor the temperature
with a cooking thermometer.
CAUTION:
Do not use a torch; it may warp the head.
Do not get the head hotter than
excessive heat may loosen the valve seats.
To avoid burns, use heavy gloves when handling
the heated cylinder head.
4. Use the driver and an air hammer working from the
camshaft side to drive the guide about 2 mm towards
the combustion chamber. This will knock off some
of the carbon and make removal easier.
VALVE GUIDE DRIVER
07742-0010100
CAUTION:
Always wear safety goggles or a face shield when
using the air hammer.
l
Hold the air hammer directly in line with the valve
guide to prevent damaging the driver.
5. Turn the head over and drive the guide out toward
the camshaft side of head.
If a valve guide still won’t move, drill it out with a
inch bit, then try again.
CAUTION: Drill guides only in extreme cases: you
could damage the cylinder head if the guide breaks.
6. Remove the new guide(s) from the refrigerator, one
at a time, as you need them.
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