C-Series Book - Industrial Engine Service

2. Unhook the spring from the pin in the base
of the governor, and with the governor
lever all the way forward toward the
carburetor, measure the distance from the
center of the hole in the governor lever to
the center of the spring pin. This distance
should be exactly 1¾" on the C-46, C-66,
C-81 and C-96 engines. On the C-101 and
C-106 engines, the distance should be
211⁄16". If the distance is not as specified
above, loosen the allen head clamp bolt
on the governor lever and set the lever for
the correct distance specified. Tighten the
clamp bolt securely.
3. Adjust the length of control rod so
that the butterfl y valve is all the way
open but not against the stop, and the
governor rod back to the position where
the butterfl y valve is just closed, but not
jammed tight against the sides of the
venturi. Then, adjust the Allen screw on
top of the governor so the butterfl y valve
cannot close any further. Lock the allen
screw with the jam nut.
If these adjustments are properly made,
the maximum no-load speed will be
4%-5% above the speed shown in the
specifi cations. It is advisable to frequently
check the operating speed of the engine
with the tachometer.
CIRCULATION OIL
Oil is drawn from the oil sump through a
fi ne screen by the oil pump; then pumped
through an externally mounted full fl ow
fi lter, into the camshaft base block to the
camshaft bearing and to the valve lifter. An
oil pressure regulating valve is located in
the camshaft base block and is accessible
without removing the camshaft Assy. Oil
bypassed by the regulating valve is sprayed
on the camshaft gear.
An additional oil bypass valve is located
in the new trochoidal oil pump to protect the
oil fi lter in extreme cold temperatures. Note
that all oil is fi ltered before going to any part
of the engine. The oil fi lter also features a
built-in bypass valve which opens in the
event of a clogged fi lter allowing continued
lubrication of the engine.
In the Arrow single cylinder engines,
the oil travels via tubing from the drilled
passage in the top of the base block to the
governor. From a tee in the camshaft base
block, oil travels to the oil collector fl ange
on the crankshaft. Oil from the collector
fl ange passes through a drilled passage in
the crankshaft to lubricate the connecting
rod bearing. Tubing, originating also at
the camshaft base block, carries oil to the
cylinder head and valve mechanisms.
OIL SUMP
The crankcase serves as a reservoir for
the engine oil supply. This large reservoir
permits longer intervals between oil
changes.
It is recommended that the oil reservoir
be drained and refi lled with new, clean oil
at regular monthly intervals, or as required
depending on site conditions. Because
oil gradually accumulates small particles
of dust, grit and corrosive material which
cause unnecessary engine wear, it should
be drained when the engine is hot, as this
aids in the removal of sediments.
The formation of sludge in the oil is due
in part to contamination caused by the
gases, leaking by the piston rings, coming
in contact with the oil and condensing. If,
when draining, the oil appears to be thick
and congealed, the oil sump should be
cleaned thoroughly. Also, remove the oil
pump strainer and clean.
The oil supply should be checked regularly,
and replenished if necessary, to maintain the
level at the sight gauge. Oil may be added
to the engine while it is running through
the ASP-1 Oil Filler. Overfi lling should be
avoided.
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1-800-331-3662 ARROW ENGINE COMPANY
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