Disassembling Crankcase; Replacing Ball Bearings - Echo PB-251 Service Manual

PB-251

7-9 Disassembling crankcase

7-10 Replacing ball bearings

ENGINE
1. Remove three crankcase screws.
2. Hold crankcase and tap crankshaft end using
plastic mallet to separate crankcase halves.
NOTE: To avoid crankcase damage, use 0.5kg (1
lb) plastic mallet and minimum force to drive it out.
3. Repeat Step 2 to remove crankshaft from another
crankcase half.
4. Clean inside of crankcase halves if dirty. Replace
as a set if damaged.
5. Inspect crankshaft for roughness (crankshaft
runout), discoloration, or other damage. Replace it
with new one as required.
1. Check ball bearings for smooth rotation.
If rough, replace it (them).
2. Pry oil seal from crankcase.
3. Remove ball bearings from crankcase halves
using bearing tool set 897701-14732 as shown.
4. Coat bearing housing in crankcase with heat re-
sistant grease.
5. Press new ball bearings into crankcase halves
using ball bearing tool as shown.
NOTE: Preheat crankcase around bearing using
floodlight or suitable heater for easier installation.
6. Check that ball bearing is seated and rotates
smoothly.
7. Install new oil seal. (Refer to "7-5 Replacing oil
seal".)
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