TM 5-3805-263-14&P-3
Position connecting rod in piston and press in wrist pin.
Install the unloader pistons in their bores with caution
against cutting the grommets or distorting the back-up
Install the plugs in the wrist pin ends (Fig. 9).
rings. Position unloader plungers in their guides and slip
them in and over the tops of the pistons.
Install piston rings in correct location with ring pipmarks
up. Stagger the position of the ring gaps.
Install the unloader spring seat in the cylinder block; a
small hole is drilled in the block for this purpose. Position
Prelubricate piston, piston rings, wrist pin and connecting
the saddle between unloader piston guides so its forks
rod bearings with clean engine oil before installing them
are centered on the guides. Install the unloader spring,
in the compressor.
making sure it seats over the spring seats both in the
block and on the saddle.
Remove connecting bolts and bearing cap from one
connecting rod. Turn crankshaft so one of its connecting
Install inlet valve seats if they have been previously
rod journals is in the downward, center position.
removed. Position and install inlet valve guides, then
Compress the rings with a ring compression tool and
drop inlet valves in their guides. There should be a loose
insert the connecting rod with piston through the top of
sliding fit between guides and valves.
the cylinder whose journal is down. Position and attach
the bearing cap to the connecting rod, making sure the
CYLINDER HEAD ASSEMBLY
bolt lock washers are properly positioned on the cap.
Tighten connecting rod bolts evenly and bend the two
If previously removed, the discharge valve seats should
new lock washer prongs up against the hex head of the
be installed. Drop discharge valves into their seats.
bolt. Install the other connecting rod and piston in the
Install discharge valve springs and cap nuts.
same manner.
Place the inlet valve springs in the cylinder head. Use a
small quantity of grease to hold them in place, just
enough grease to keep the springs from falling out. Place
cylinder head gasket on cylinder block. Carefully align
cylinder head assembly on block and install cap screws
with lock washers.
Tighten securely and evenly cap screws that hold
cylinder head to block.
FIGURE 10
UNLOADER MECHANISM
UNLOADER MECHANISM (Fig. 10)
The unloader pistons and their bores must be lubricated
with special lubricant dimethyl polysiloxane prior to
installation. If new unloader kits are being installed, the
pistons in the kit are already lubricated.
3-140
