IMT Diamond Air DA435ELW, Service Manual, Page: 20 / 24

DA435ELW: 99900917: 5-4
5-4. CRANKSHAFT AND BEARING
REPLACEMENT
If it is necessary to replace the crankshaft, related
components must also be replaced. Replace both
bearings, both races, the key, pump collar and pump
drive pin.
NOTE
DEPENDING ON THE CONDITION OF THE
CRANKSHAFT, BEARING MAY BE REPLACED
WITHOUT REPLACING THE CRANKSHAFT.
REPLACE THE BEARING RACES WHENEVER THE
BEARINGS ARE REPLACED.
1. Remove the pulsation tank, both heads,
cylinders, and pistons. Refer to the instructions in
section 5, paragraph 2.
2. Remove the bolts on the connecting rods, and
lift them out. Reassemble the connecting rods to be
certain that the matched parts remain together on the
same crankshaft journals.
3. Remove the pump cover, oil pump, sleeve,
spring, and rear bearing housing.
4. Remove the clutch and pulley assembly, and the
front bearing housing.
5. Pull the crankshaft from he crankcase.
6. Remove all gasket material with a single edged
razor blade, or sharp putty knife.
CAUTION
DO NOT GOUGE THE MACHINED SURFACES
WHEN REMOVING THE GASKETS. THIS MAY
CAUSE LEAKS.
7. Press the bearing races out of the bearing
housing.
8. Press the tapered roller bearings off of the
crankshaft if only the bearings are being replaced. If
the crankshaft is to be replaced, discard the entire
assembly.
9. Press the new bearings into position.
NOTE
THE CRANKSHAFT SHOULD HAVE NEW
BEARINGS INSTALLED. IF NOT, PRESS THE NEW
BEARINGS INTO POSITION ON THE CRANKSHAFT.
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10. Generously oil the front bearing race and install
the front bearing housing with gasket. Torque the
bolts to 180 in-lbs. Torque the bolts as shown in the
pattern below.
FIGURE E-3. BEARING HOUSING
TORQUE SEQUENCE
FIGURE E-4. ROD ALIGNMENT
11. Slide the crankshaft into the crankcase.
Generously lubricate the bearing race and install the
rear bearing housing and gaskets.
NOTE
GASKET KITS ARE SUPPLIED WITH TWO (2) EACH
OF .006, .010, .015, AND .020 GASKETS. USE
THESE REAR BEARING GASKETS IN ANY
COMBINATION AND QUANTITY TO LIMIT ALL PLAY
FRONT TO REAR, BUT STILL ALLOW THE
CRANKSHAFT TO TURN FREELY.
12. Install the oil pump as indicated in Section 5-3.
13. Install the connecting rods. Thoroughly oil the
crankshaft and rods before installing them. When
installing the rods, make certain that the tabs are
aligned on the same side of the rod as shown below.
14. Install the pistons, rings, heads and pulsation
tank.