Instructions / Assembly

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Phenomenon Possible causes Remedy
1. Carburetor
1) Low idling speed Adjust
2) Carburetor slow system passage clogged Check and clean
2. Intake system 1) Air mixing from connecting portion of air intake system Check, tighten or replace gasket
3. Cylinder head 1) Cylinder head gasket faulty (blow-by) Replace
4. Valve system
1) Improper valve clearance Adjust
2) Leakage from valve seat Adjust valve seat contact
3) Excessive clearance between valve stem and guide Replace
5. Ignition system 1) Weak ignition spark Check and replace spark plug
9-5 ROUGH IDLING
9-6 HIGH ENGINE OIL CONSUMPTION
Phenomenon Possible causes Remedy
1. Oil leakage
1) Loosen drain plug Tighten
2) Drain plug gasket damaged Replace
3) Incorrect oil filter fitting Repair
4) Loosen main bearing cover bolts Tighten
5) Main bearing cover gasket damaged Replace
6) Crankshaft oil seal damaged Replace
2. Oil dilution
1) Piston oil ring faulty Replace
2) Piston rings seizure, wear or poor contact Replace
3) Excessive wear of piston and cylinder Replace
4) Excessive wear of valve stem Replace
5) High oil level Adjust oil level
6) Breather faulty Repair or replace