Onan NH User Manual

INSPECTION AFTER OVERHAUL
For no-load test, the starting motor is wired as
shown in Figure
49 and run. The value of the
meter reading at this condition should be as
follows:
Begin Spec
B
Voltage 10.5 11.5
RPM 5000 3700
Max. Current
Draw (Amp)
53 60
Spec A Only
1.
AMMETER
SWITCH
INDICATOR
FIGURE 49. WIRING STARTER FOR NO-LOAD TESTS
The conductor for this test should be large enough in
diameter and as short as possible.
If anything is wrong in
the above test, inspect the following items:
Annealed brush springs
Improperly sealed brushes
Insufficient armature endplay
Shorted, open, or grounded armature
Grounded or open field coil
Poor electrical connection
Dirty commutator
2.
To adjust pinion clearance, connect the battery to
thestarting motorasshown in Figure50.This will
allow the pinion of the starting motor to slide and
stop. In this state, measure the clearance between
the end of the pinion and pinion stop when the
pinion
is pushed lightly toward the commutator
end. Clearance should be
0.02 to 0.06 inch (0.51
to 1.52 mm). Adjust for proper clearance by
removing the solenoid switch attaching screws
and select the proper thickness of the fiber
packings shown
in Figure 51.
FIBER PACKINGS
FIGURE 51. ADJUSTING PINION CLEARANCE
CHECKING GEAR LASH
Always check starter-to-flywheel gear lash when
reinstalling the starter on the engine. Lash should
also be checked if the starter binds or slips during
cranking or
is excessively noisy. Proceed as follows:
1.
2.
3.
4.
5.
Before installing thestarter, make sure the starter
mounting surfaces on the engine base are free of
dirt and oil to assure good electrical contact.
Install the starter motor and tighten the mounting
bolts just enough to hold the starter in place.
Remove the spark plugs from the engine to allow
free movement of the flywheel.
Manually pull the starter pinion gear outward on
its shaft
so that its teeth mesh fully with those on
the flywheel.
Measure the amount of free travel (lash) between
the pinion gear teeth and the ring gear teeth, as
shown in Figure52. Proper lash isO.O20+0.010 in.
(0.51+_0.25 mm). Loosen and adjust the starter
motor as necessary to obtain the correct setting.
6. Torque down thestarter mounting bolts and rein-
stall the engine spark plugs.
FLYWHEEL
RING GEAR
0.020 f 0.010'' (0.51 f 0.25 mm)
FLYWHEEL GEAR FREE TRAVEL WHE
ENGAGED WITH STARTER G.EqR
STARTING MOTOR
PINION GEAR
FIGURE 50. BATTERY CONNECTIONS
38
FIGURE 52. CHECKING STARTER GEAR LASH

Onan NH Specifications

General

Brand	Onan
Model	NH
Category	Engine
Language	English