Onan DJA Series User Manual

I Ojl STARTING MOTOR
AND FLANGE
'SHIMS
Required on some early models.
Be sure to install same number
of shims removed.
FIG. 9-4
Field Coils: Using a 120-volt test lamp and probes, check
the field coils for grounding to the motor frame or open
circuit. Inspect all connections to be sure they are properly
clini hed and soldered. Inspect the insulation for evidences
of damage. The only way to check for field coil shorts is to
use the lest at the beginning of this section.
Bearings: If either the front or rear bearings show excessive
wear, replace them. Drive the old bearings out, and using an
arbor press and the proper arbor, press new bearings into
place. The outer pinion bearing must be flush with the
bearing bore on the inside of the bearing.
Brushes: Check the brushes for wear or improper seating.
They should slide freely in their holders. Check the brush
spring tension with a spring scale. To change springtension,
twist the spring at the holder with long nose pliers.
If brushes are excessively worn, replace them.
Some brushes are soldered to the field coil lead. Unsolder
the lead and open the loop in the field coil lead. Insert the
new brush pigtail completely into the loop and clinch before
resoldering. A good soldering job is necessary to insure
good contact and low voltage drop across the connection.
Over-Running Clutch: Clean the clutch thoroughly but do not
dip in solvent. It cannot be repacked with jjease.
It should slide easily on the armature shaft with no binding.
Turn the pinion; it should rotate smoothly, but not necessarily
, freely. Reverse the direction a few times and it should
instantly lock and unlock. Replace the clutch if operation
is defective or pinion is worn or damaged.
Shifting Solenoid: Check to be sure plunger moves freely in
coil. Measure the pull-in coil current draw by connecting a
batteiy, voltmeter and ammeter to the control terminal and
the terminal to the motor. Measure the hold in coil draw
from the control terminal to ground. Inspect the switch for
corrosion and clean the contacts if necessary. Replace the
solenoid if the current draw is not within limits when
cleaned.
ASSEMBLY, STARTING MOTOR
Before assembling, soak.the bronze bearings in oil. They
are absorbent bearings, designed to hold up to 25% of their
own weight in oil. Be sure the felt oil pad is in the outer
end of the commutator end bearing.
When the motor is assembled, check the armature end play.
It should be.between .005" and .030". Adjust end play by
adding or removing washers on the commutator end of the
armature.
Before installing, check the pinion clearance. Proper
clearance is important to insure starter engagement. Press
on solenoid core to shift the pinion into full mesh and
measure the clearance between pinion and pinion stop (Fig.
9-3). This should be between .070" and .120" (as near to
.070" as possible). Adjust the link screw on the end of the
solenoid plunger for proper clearance.
Important: On units built, prior to serial #679677, it was
necessary to maintain the gap between ring gear and starter
pinion in the relaxed position at less than 1/8" to insure
starter engagement. When installing these motors, check
Ais gap. li it is too great, a shim kit is available to reduce
it (Fig
r
9^).
25

Onan DJA Series Specifications

General

Brand	Onan
Model	DJA Series
Category	Engine
Language	English