Onan DJA Series User Manual

GEAR COVER
c
•-INSTALL OIL SEAL
FLUSH WITH THIS
SURFACE
•OIL SEAL
-THIS SURFACE MUST
BE CLEAN BEFORE
INSTALLING SEAL
FIG. 13-2
wom. Drive the old seal out from inside the gear cover.
Lay the cover on a board so the seal boss is supported.
Using an oil seal driver, insert the new seal from the inside
with rubber lip toward outside of gear cover (open side of
seal inward) and drive it flush with the outside surface.
During gear cover installation, use the driver to protect the
oil seal.
Assembly, Gear Cover:
1. Work the governor shaft to chsck for binding and see
that the governor-shaft-end-thrust ball is in place (Fig.
13-1). Later models have larger ball which will not
fall out.
2. Turn governor yoke so the smooth side is toward
governor cup.
3. Turn the governor cup so the stop pin in the gear cover
will fit into cne of the holes in the cup surface (Fig.
13-D. Measure the distance from the end of the stop
pin to Lhe mounting face of the cover. It should be
25/32". If it is not, replace the pin. Pin should be
positioned with open end facing crankshaft seal.
4. Coat the oil seal lip with oil or grease. Set a piece of
shim stock over the crankshaft keyway to protect the
seal and install the gear cover. Tighten the mounting
screws to specified torque. Before tightening screws,
bf sure the stop pin is in the governor hole.
GOVERNOR CUP
To rr move the governor cup, remove the snap ring from the
camshaft center pin and slide the cup off. Be sure to catch
the ten flyballs that will fall out when the cup is removed.
Repair: Replace any flyballs that have flat spots or
grooves. Replace the cup if the race surface is grooved or
rough. The governor cup must be a free spinning fit on the
camshaft center pin, but should be replaced if excessively
loose or wobbly.
Check the distance the center pin extends trom the camshaft
gear, this distance must be 25/32 to give the proper travel
distance for the cup. If it is less, the engine may race; if
WHEN GOVERNOR IS
PROPERLY ASSEMBLED
THE DIMENSION SHOWN
ON DRAWING WILL BE
AS INDICATED
CENTER PIN
SNAP RING
GOVERNOR CUP -
GOVERNOR FLYBALL
FIG. 13-3
36
more, the cup will not hold the balls properly. If the
distance is too great, drive or press the center pin in. If it
is too small, replace the pin; it cannot be'removed without
damaging the surface.' Iri some cases, if the distance is too
small, the head of the governor cup can be ground to give
the necessary 7/32" travel distance.
Installation: To install the governor assembly, tip the front
of the unit upward. Set the flyballs in their recesses and
position the governor cup on its shaft. Finally, brush with
heavy grease and install the snap ring on the center pin.
CAMSHAFT
The camshaft is a 1-piece machine casting, driven through
gears by the crankshaft. It rides on sleeve bearings pressed
into the crankcase.
•
In addition to providing a means of opening and closing the
valves, the camshaft operates the injection pump and fuel
transfer pump.
Removal:
1. Remove the rocker arms and push rods from the valve
chambers.
2. Remove the injection pump and fuel transfer pump from
the engine.
3. Remove the crankshaft gear retaining washer by remov-
ing the lock ring on the crankshaft.
4. Lay the engine on side to avoid dropping tappets and
removethe camshaft assembly as a group. If necessary,
pry it out with a screwdriver between the camshaft gear
and crankcase.
5. Remove the valve tappets. These can be removed only
from the camshaft end of the push rod holes.
Repair: If a lobe has become slightly scored, dress it
smooth with a fine stone. If the camshaft is badly worn or
scored, replace it. After installing a new camshaft, retime
the injection pump to the engine.
Camshaft Gear: This gear is a pressed fit on the camshaft

Onan DJA Series Specifications

General

Brand	Onan
Model	DJA Series
Category	Engine
Language	English