© 2007 ICS, Blount Inc. F/N 71537 Oct 07
TITLE 613GC SERVICE MANUAL

72

25. DIAGRAMS

25 This section provides several flowcharts to aid diagnosing common problems.

CHECK POSSIBLE CAUSE REPAIR

The engine runs rough at
all speeds
The engine is overheating.
• Operator is overworking
the saw.
• Carburetor mixture is too
lean.
• Incorrect fuel/oil ratio.
• Flywheel fins are clogged.
• Air deflector is missing.
• Cylinder fins are clogged
Poor acceleration.
• Dirty or clogged air filter.
• Clogged fuel filter.
• Incorrect carburetor tune.
• Plugged tank breather.
• Blocked pulse tube.
Uneven idle or engine
may “run away”
• Air leak at intake boot,
cylinder gasket, or
crankcase gasket.
• Faulty carburetor
diaphragm.
Diamond chain moves
at idle.
• Idle speed too high.
• Broken clutch spring.
Excessive vibration. Y ES
• Damaged shock absorber.
• Damaged or broken
flywheel fins.
• Bent crankshaft.
• Replace shock absorbers
• Replace flywheel.
• Replace crankshaft.
• Adjustidlespeed.
• Replace clutch spring.
YES
• Inspect air intake boot.
• Pressure test crankcase.
• Replace carburetor.
YES
• Clean or replace the air filter.
• Replace fuel filter.
• See Carburetor Tuning section.
• Repair or replace fuel tank
breather.
• Replace pulse tube.
YES
• See Operator’s Manual.
• See Carburetor Tuning section.
• See Saw Specifications section.
• Clean flywheel fins with wire
brush.
• See Starter Cover section.
• Clean cylinder fins.
YES
• Dirty or clogged air filter.
• Water has been ingested.
• Loose or dirty spark plug.
• Clean or replace the air filter.
• Inspect air intake sysetm for water.
• Inspect fuel system for water.
• Tighten, clean, or replace spark
plug.
YES
A dirty air filter is the #1 reason for engine problems.