Caution: The cap and body seat
A f t e r refacing the valves, check the
must be an airtight seat, since it is a
thickness from the top of the head to
point at which the energy cell is sealed
the edge of the refaced outer surface.
i n t o the head and any leakage would
This can be accomplised by comparing
cause burning of the surrounding
t h e refaced valve with a new one. If
metal in a short time.
t h e refaced valve has 50 percent less
margin, replace the valve.
(8) A f t e r t h e v a l v e s h a v e b e e n r e f a c e d
80. Cylinder Head Assembly Reassembly
a n d the valve seats in the block re-
finished, the valve and seats should be
ground (lapped). Place a small
assemble the cylinder head assembly in the re-
amount of medium grade grinding
v e r s e order.
compound around the face of the
valve. Place a light spring under each
C a u t i o n : Make certain that the energy cells
valve and lap into place.
have been torqued from 35 to 40 foot-pounds to
Note. Avoid continuous round-and-round
i n s u r e against possible leaking from the com-
motions that would cut grooves in the valve
b u s t i o n chamber at either the seat where the
or seat. Rotate only part of a turn with a
b o d y contacts the head or the contact surface
suitable tool, then raise it off the seat and
between the cap and the body.
move it to a new position and then repeat
(9) T e s t e a c h v a l v e f o r a t i g h t s e a t b y
m a k i n g pencil marks across the face
inder head assembly on the engine.
of the valve at short intervals, and
t h e n rotate the valve against its seat
( 2 ) Install the rocker arm assembly (par.
f o r part of a turn with firm pressure
a n d again lift out and observe if the
(3) If water pump was removed, install
pencil marks are all rubbed out on the
t h e pump (par. 48).
c o n t a c t surfaces; if not, regrind until
fold (TM 5-3820-205-20/l).
t h i s test shows a gastight mating of
( 4 ) Install the intake and exhaust mani-
valve to seat. It is imperative that
fold (TM 5-3820-205-20/l).
t h e valves then be assembled in the
same seats to which they were ground.
(5) Install the water manifold (TM 5-
(10) Lap the energy cell body into the head
w i t h valve grinding compound using
(6) Install the fuel injector assemblies
the puller or a piece of wood of such
s i z e that it can be screwed into the
(7) Adjust the valves (TM 5-3820-205-
threads in the energy cell, and lapped
in the same manner as you would a
valve in a cylinder head.
( 8 ) Install the valve covers (TM 5-3820-
(11) T h e c o n t a c t s u r f a c e w h e r e t h e c a p
s e a t s on the body must be lapped to
(9) Install the engine housing (TM 5-
make an airtight seat.
Se c t ion
V lBRAT lON
DRI V E
disks. One disk is mounted rigidly, while the
other is free to rotate, limited only by the
The vibration damper is mounted on the
f r o n t of the engine drive pulley. It is a fly-
w h e e l - t y p e disk that is made from two steel
v i b r a t i o n damper is to reduce or damper tor-