Onan NHC Series Operator's/Service Manual And Parts Catalog page 155

KEEP SHAFTS OF ENGINE
AND LOAD P A R A L L E L ,
z
KEEP PULLEYS ALIGNEt
WITH • EACH OTHER
BELT IN TIGHTENED
y
I D L E R PULLEY
POSITION - PULLING
LOAD
ENGINE
PULLEY
LOAD
PULLEY
B E L T , IN LOOSENED
POSITION - NOT
PULLING LOAD
BRACKET TO KEEP
B E L T OFF ENGINE
PULLEY
FIGURE I. DRIVE B E L T INSTALLATION
Comply with the following installation requirements:
1. The shafts of the engine and the load must be
parallel with each other..
2. The pulleys of the engine and the load must be
in alignment.
3. Mount the engine pulleys as close to the engine
as possible.
4. I f the installation permits, belts should run hori-
zontally.
5. Some method of disconnecting the load for starting
is recommended. If a clutch is not used, a belt-
tightener idler arrangement can be used.
Flexible Coupling: If a flexible coupling engine-to-
load drive is used, the load shaft must be in line and
centered with the engine shaft (Figure 2).
ENGINE POWER
T A K E - OFF
SHAFT
F L E X I B L E
COUPLING
Reduction Gear Drive: Reduction • gear drives are
mounted at the factory (when ordered). The method
of connecting the load is the same as when connecting
directly to the engine shaft.'
Clutch Installation: A Rockford Clutch can be installed
at the factory or i n the f i e l d . Install the clutch accord-
ing to the following instructions and Figure 3.
Provide room for the clutch adapter casting by plugging
the wet holes with a 3/8-16 x 1 / 2 " slotted headless
set screw. Apply sealing compound to the threads and
install screw flush with the cylinder block.
D r i l l a 1 3 / 6 4 " hole (or filed slot) in the crankshaft
for the clutch set screw. Locate center of hole 1 1 / 3 2 "
from the end and directly opposite the keyway iri the
crankshaft.
Install the clutch adapter, with drain slot downward,
using two cap screws 3/8-16 x 2 " on the lower and
one cap screw 3/8-16 x 1-3/4 " o n the upper #2 cylinder
side (cylinder nearer clutch). Install the 3/8 x 3 - 7 / 8 "
stud through the adapter into the engine block upper
remaining hole. Use a lock washer on each .assembly
•screw. Use a f l a t washer and a lock washer under t h e '
stud nut.
Install the crankshaft key. Remove the clutch set
screw. Insta.ll the clutch assembly (less housing) to
the crankshaft, driving it on carefully with a soft-faced
hammer until set screw, hole is aligned. Install set
screw to bottom i n crankshaft hole, then back i t out
one f u l l turn. Tighten clutch retaining screws u n t i l
clutch is clamped securely to crankshaft. Lock the
screws and tighten the set screw.
KEYWAY
i
DRILL 13/64" HOLE
1/8" DEEP
CRANKSHAFT STUB SHAFT
CLUTCH CLUTCH
ASSEMBLY HOUSING
•I 1/32"
A867 CLUTCH
ADAPTER
SET SCREW
POWER
T A K E - O F F
SHAFT
FIGURE 2. F L E X I B L E COUPLING
FIGURE 3. CLUTCH INSTALLATION