down on a wooden bench or protective
surface to prevent marring milled surface.
(4) Assemble lower valve spring guide over
(5) Assemble springs, reground valve heads
seat deeper in cylinder head causing valve
stem to protrude further above the guide.
This allows spring to extend beyond length
limits and causes weak spring action.
There- fore, up to 1/16 inch (1.59 mm) of
spacers may be used to reduce valve spring
length. See tabulated data in Chapter 1.
compressed spring to become a solid
(6) Assemble upper valve spring retainer and
use a valve spring compressor stand and
springs. Insert new half collets.
(7) Replace all pipe plugs. Use sealing tape or
lead sealer to prevent leakage. Torque plug
as follows: (Torque values are given in foot-
pounds followed in parentheses by the
metric equivalent in joules.)
(8) Install pipe plugs in fuel inlet and drain
fittings in same position, as removed, in
each cylinder head. Position and secure
water header plates with new gaskets.
(9) Install an injector sleeve holding tool or a
scrap injector and cup assembly in each
injector sleeve. Tighten sleeve holding tool
to 7 to 8 foot-pounds (9 to 11 joules) to seal
lower end of injector sleeve, or install
injectors and secure with capscrews torqued
to same value.
(10) Test cylinder heads for leaks at 35 to 85
psi (241 to 586 kPa) using the hydrostatic
tester and, if possible, at 175 to 200xF (79
to 93xC) water temperature. Check
carefully around valve seats and injector
sleeve seats for any cracks.
(11) Open water outlet valve of test fixture;
check for free water circulation through
SPRINGS. To service the intake and exhaust valves
and springs, refer to figure 13-41, and proceed as
Removal. Proceed as follows:
(1) Using a valve spring compressor, compress
valve spring, remove half collets, retainers,
springs, valve spring guides, and valves.
(2) Place valves on a numbered board for
(1) Clean valves with buffer and polish with
(2) Inspect, then discard if heads are cupped,
cracked, pitted, or worn too thin to regrind
within limits. Check valve head rim
thickness (1, figure 13-45). Discard valve if
rim is less than 0.105 inch (2.67 mm).
(3) Inspect then discard if stem is scored or
worn beyond worn limits; new dimensions
are 0.450 to 0.451 inch (11.43 to 11.45
(4) Inspect then discard if collet recesses are
worn so new collets will not fit securely in
c. Testing. Refer to paragraph 13-27 f (29) for