Subaru Robin EX13 User Manual
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Problem and possible cause
Remedy
1. Oil leakage
1) Loose oil drain plug
Tighten
2) Faulty oil drain gasket
Replace
3) Loose main bearing cover bolts
Tighten
4) Faulty main bearing cover gasket
Replace
5) Crankshaft oil seal (front, rear) defect
Replace
2. Oil up
1) Faulty piston oil ring
Replace
2) Piston ring seizure, wear or poor contact
Replace
3) Excessive wear of piston and/or cylinder
Replace
4) Faulty stem seal
Replace
5) Excessive oil level
Adjust oil level
6) Breather defect
Repair or replace
1. Fuel system
1) Clogged air cleaner
Clean or replace
2) Faulty needle valve and/or high fuel level in
float chamber
Repair or replace
3) Choke does not open fully
Repair or replace
2. Engine core components 1) Low compression
Check and repair
2) Overcooling
Check and adjust load
and/or engine speed
1. Ignition system problems 1) Loose ignition system wiring
Inspect and tighten
2) Improper or faulty spark plug
Clean or replace
2. Fuel system problems
1) Lean or rich fuel/air mixture
Clean, adjust or replace
carburetor
2) Carburetor contamination
Overhaul or clean
3) Dirty or clogged fuel lines
Clean or replace
4) Air mixing from air intake system joints
Tighten; replace gasket
3. Cylinder head
1) Carbon deposit in combustion chamber
Clean
2) Leakage from cylinder head gasket
Replace
4. Valve system problems
1) Improper valve clearance
Adjust
2) Valve heat deterioration
Replace
3) Worn or broken valve spring
Replace
4)Improper valve timing
Adjust
Excessive engine oil consumption
High fuel consumption
Abnormal engine noise