BENDIX TU-FLO 400-500-1000 AIR COMPRESSOR Manual page 12

Slightly worn or scratched inlet valves can be reclaimed by
lapping them on a piece of fine crocus cloth on a flat surface,
but it is suggested that new inlet valves be installed.
ASSEMBLY
INSTALLING CYLINDER BLOCK
Position cylinder block gasket and block on crankcase
according to markings made prior to disassembly. Using
cap screws with lock washers, secure cylinder block to
crankcase.
INSTALLING CRANKSHAFT
If the crankshaft is fitted with oil seal rings, install rings.
Position ball bearings and crankshaft in crankcase, making
sure the drive end of the crankshaft is positioned as marked
before disassembly.
If one end of the crankcase is counterbored for holding a
bearing, be sure the crankshaft is installed through the correct
end of the crankcase.
Carefully press crankshaft and bearings into crankcase using
arbor press.
Position a new rear end cover gasket, when used, over the
rear end of the crankcase, making sure the oil hole in the
gasket lines up with the oil hole in the crankcase. Position
end cover with oil seal ring, if used, installed over crankcase
and end cover gasket. The end cover should be positioned
correctly in relation to the oil holes in the gasket and
crankcase. Secure end cover to crankcase with cap screws
and lock washers.
If the opposite end cover requires an oil seal which was
removed on disassembly, a new seal should be pressed
into end cover. Position new end cover gasket and carefully
install end cover over crankshaft and to crankcase, avoiding
damage to the seal. Secure end cover with cap screw and
lock washers.
PISTONS AND CONNECTING RODS
If new wrist pin bushings are to be used, they should be
pressed into the connecting rods so that the oil hole in the
bushing lines up with the one in the rod. The new bushings
should then be reamed or honed to provide between 0.0002
in and 0.0007 in. clearance on the wrist pin. Position
connecting rod in piston and press in wrist pin so that
lockwire hole in the pin aligns with that of the piston. Install
new lockwire through piston and wrist pin and lock same by
snapping short end into lockwire hole at the bottom of the
piston (Fig. 7). Teflon plugs in wrist pin ends may be used
instead of the lockwires (Fig. 22).
Install piston rings in correct location with ring pipmarks up
(Fig. 24). Stagger the position of the ring gaps.
Prelubricate piston, piston rings, wrist pin and connecting
rod bearings with clean engine oil before installing them in
the compressor.
12
Remove connecting bolts and bearing cap from one
connecting rod. Turn crankshaft so one of its connecting
rod journals is in the downward, center position. Compress
the rings with a ring compression tool and insert the
connecting rod with piston through the top of the cylinder
whose journal is down. Position and attach the bearing cap
to the connecting rod, making sure the bolt lock washers
are properly positioned on the cap. Tighten connecting rod
bolts evenly and bend the two new lock washer prongs up
against the hex head of the bolt. Install the other connecting
rod and piston in the same manner.
FIGURE 25 - UNLOADER MECHANISM
UNLOADER MECHANISM (Fig. 25)
The unloader pistons and their bores must be lubricated
with special lubricant piece number 239379 (dimethyl
polysiloxane) prior to installation. If new unloader kits are
being installed, the pistons in the kit are already lubricated.
Install the unloader pistons in their bores with caution against
cutting the grommets or distorting the back-up rings. Position
unloader plungers in their guides and slip them in and over
the tops of the pistons.
Install the unloader spring seat in the cylinder block; a small
hole is drilled in the block for this purpose. Position the
saddle between unloader piston guides so its forks are
centered on the guides. Install the unloader spring, making
sure it seats over the spring seats both in the block and on
the saddle.
Install inlet valve seats if they have been previously removed.
Position and install inlet valve guides, then drop inlet valves
in their guides. There should be a loose sliding fit between
guides and valves.
CYLINDER HEAD ASSEMBLY
If previously removed, the discharge valve seats should be
installed. Drop discharge valves into their seats. Install
discharge valve springs and cap nuts.
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.