Robin America EK13, Service Manual

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63
Problem and possible cause Remedy
1) Loosen spark plug Retighten; replace gasket
2) Leakage from cylinder head gasket Retighten; replace gasket
3) Piston ring seizure or wear Replace
4) Piston or cylinder wear Repair or replace
5) Incorrect valve and seat contact Repair or replace
6) Valve stem seizure Repair or replace
1. Insufficient
compression
7) Improper valve clearance Adjust
1) Faulty spark plug Replace
2) Faulty ignition coil Replace
3) Improper air gap between ignition coil and flywheel Adjust
2. Ignition system
problems
4) Demagnetization (flywheel magneto) Replace
1) Carburetor clogged Overhaul, clean
2) Fuel strainer and/or hose clogged Clean or replace
3) Air in fuel lines Check and retighten joints
3. Fuel system
malfunction
4) Poor quality gasoline or water in gasoline Replace
1) Air cleaner clogged Clean or replace
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4. Low air intake volume
2) Throttle valve malfunction Repair or replace
1) Cooling air flow obstructed at inlet or cylinder baffle
portion
Clean
2) Poor quality engine oil Replace
3) Lean fuel/air mixture Check and adjust carburetor
4) Excessive back pressure of exhaust system Check and clean or replace
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1. Engine
5) Overloading Adjust to rated load
1) Low idling speed Adjust
2) Slow system passage clogged Check and clean
1. Carburetor system
3) Hunting after engine stop
Check or replace
O-ring (spacer)
2. Intake system
1) Air mixing from air intake system joints
Check and tighten;
replace gasket
3. Cylinder head 1) Gasket faulty (blow-by) Replace
1) Improper valve clearance Adjust
2) Leakage from valve seat Repair
4. Valve system
3) Excessive clearance between valve stem and guide Replace
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ough
I
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5. Ignition system
1) Weak spark
Check; adjust or replace
plug