Hudson 1936 Six, Owner'S Manual

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Crankshaft, Connecting Rods and Pistons
The crankshaft is a heavy forging with integral compensating weights. Full
compensation and a torsional dampener mounted on the front insures free running
of the crankshaft under all operating conditions. The main bearings are removable
bronze backed, virgin babbitt and are fitted to .001" clearance and provided with
shims for adjustment. The working member of the dampener is rubber, fully
enclosed, requiring no adjustment.
The connecting rods are steel forgings carrying spun virgin babbitt bearings in
the lower end fitted with a clearance of .001" and having shims .provided w for
adjustment. The upper end is fitted with a bronze bushing to which the piston pin
is fitted with .0003" clearance.
The pistons are of silicon aluminum alloy of new design. This alloy is hard,
lighter than aluminum and dissipates heat rapidly. The piston is "T" slotted to
compensate for expansion; cam ground to give full bearing on the cylinder wall;
and is fitted with two compression rings and one oil control ring above the piston
pin and one oil control ring below. With this arrangement all of the rings are
located somewhat lower down on the piston, with the result that cooler operating
conditions and better oil control are obtained. The piston is attached to the
connecting rod by a full floating pin, which is honed to give a perfect bearing in
the diamond bored piston bosses. The piston pin is a snug fit in the piston bosses
when the piston is heated to 200° F.
This piston design permits fitting to the cylinder with a clearance of .002". The
pistons are removable from the top of the cylinder bore.
The camshaft is Electric Furnace Alloy with hardened bearing and cam surfaces.
End play is prevented by a spring and plunger pressing against the front end of the
shaft.
Valve Tappet Adjustment
The valves, which are silicon chromium steel, are operated by the cams through
adjustable tappets. The tappets should be adjusted while the engine is at normal
operating temperature. To adjust the tappets, remove the engine side cover plates
(right side of engine below intake manifold) and insert a feeler gauge between the
top of the tappet screw and bottom of the valve stem while the engine is running.
The valve tappets should be adjusted to a feeler gauge clearance of .006" on the
intake valves and .008" on the exhaust valves. The tappet screw locking nut should
be tightened securely after adjustment. The tappet clearance is important and
should be set accurately to the recommended dimensions.
Valve Timing
The valve timing is determined by the meshing of the crankshaft and camshaft
gears. The tooth of the crankshaft gear with the punch mark on the front face
should mesh between the two punch marked teeth of the camshaft gear.
Lubrication System
The Hudson Duo-flo Automatic Lubrication System gives a positive flow of oil
to every working part of the engine from the moment of starting throughout the
period of operation. It also, through in-built features, conditions the oil so that all
oil supplied by the oscillating plunger pump is cooled and freed of solid matter and
diluents.
1 4 H U D S O N S I X