Chainsaw Repair Manual Wildcat 38cc

The Wildcat 38cc chainsaw is a lightweight, professional-grade chainsaw designed for demanding cutting tasks. This manual provides comprehensive instructions for maintenance, troubleshooting, and repair of the Wildcat 38cc model. Below are key sections covering safety, specifications, maintenance procedures, troubleshooting, and parts information.

1. Safety Precautions 2. Specifications 3. Maintenance Schedule 4. Engine Repair 5. Chain & Bar Maintenance 6. Carburetor Adjustment 7. Ignition System 8. Fuel System 9. Troubleshooting Guide 10. Parts Diagram 11. Warranty Information

Safety Precautions

Always prioritize safety when operating or repairing the Wildcat 38cc chainsaw.

Safety Item	Description
Protective Gear	Always wear safety glasses, gloves, hearing protection, and chainsaw chaps.
Work Area	Ensure clear work area, secure footing, and no bystanders within 15 feet.
Chain Brake	Test chain brake before each use; engage when not cutting.
Fuel Safety	Refuel in well-ventilated area with engine off and cool.
Kickback Zone	Avoid contact with upper quadrant of guide bar tip.
Transport	Engage chain brake and install scabbard when carrying.
Maintenance	Disconnect spark plug before performing any repairs.
Sharp Chain	Keep chain sharp; dull chains increase kickback risk.
Bar Oil	Check bar oil level before each use; use proper chainsaw bar oil.
Starting	Start on ground or firmly held, with chain clear of objects.

Specifications

Engine Displacement: 38cc, 2-stroke.
Power Output: 2.1 HP at 9,500 RPM.
Fuel Capacity: 14.9 fl oz (440 ml).
Oil Capacity: 8.5 fl oz (250 ml).
Guide Bar Length: 16 inches (standard), compatible with 14"-18".
Chain Pitch: 3/8" low-profile.
Chain Gauge: 0.050".
Weight (dry): 10.1 lbs (4.6 kg).
Ignition System: Electronic CDI.
Carburetor: Walbro WT series, adjustable H/L/idle.
Spark Plug: NGK BPMR7A, gap 0.020".

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Daily/Before Use: Check chain tension, bar oil, fuel level, air filter, and chain sharpness.
Every 10 Hours: Clean air filter, check spark plug, inspect chain brake function.
Every 20 Hours: Clean cooling fins, check fuel filter, inspect bar for wear.
Every 50 Hours: Replace spark plug, clean carburetor, check clutch and sprocket.
Every 100 Hours: Decarbonize exhaust, replace fuel filter, inspect ignition system.
Seasonal: Drain fuel for storage, lubricate clutch bearing, full inspection.

WARNING! Always use genuine Wildcat parts for replacement. Improper maintenance voids warranty.

Engine Repair

Common engine repairs include piston/cylinder replacement and crankcase servicing.

Compression Test: Should read 120-150 PSI. Low compression indicates worn piston/rings.
Piston Replacement: Remove cylinder head; inspect cylinder for scoring; replace piston assembly.
Crankcase Seals: Leaking seals cause air leaks and poor performance. Replace if damaged.
Bearings: Check main bearings for play; replace if rough or noisy.
Gaskets: Always replace gaskets during engine disassembly.

CAUTION! Engine repairs require specialized tools. Refer to torque specifications.

Chain & Bar Maintenance

Proper chain and bar care extends life and improves cutting performance.

Chain Tension: Adjust so chain snaps back when lifted from bar; not too tight.
Sharpening: Use correct round file size (5/32" for 3/8" LP); maintain 30° cutting angle.
Depth Gauges: File depth gauges (rakers) to 0.025" below cutter height.
Bar Maintenance: Flip bar weekly for even wear; clean bar groove; dress rails if burred.
Sprocket: Replace drive sprocket every 2-3 chains; inspect for wear.

Tip: Lubricate bar nose sprocket bearing regularly with grease gun.

Carburetor Adjustment

Proper carburetor tuning ensures smooth operation and prevents engine damage.

Screw	Function	Initial Setting
L (Low)	Idle and low-speed mixture	1-1/4 turns out
H (High)	High-speed mixture	1 turn out
T (Idle)	Idle speed	Adjust until chain stops moving

Start with warm engine in well-ventilated area.
Adjust L screw for fastest idle, then rich slightly.
Adjust H screw for maximum RPM, then rich 1/8 turn.
Set idle speed so chain doesn't move at idle.
Test acceleration; adjust if hesitates or bogs.

WARNING! Running too lean damages engine. Always finalize adjustments under load.

Ignition System

The CDI ignition system provides spark for combustion.

Spark Plug: Replace annually or every 50 hours. Gap: 0.020".
Ignition Coil: Air gap should be 0.010" (0.25mm). Adjust with feeler gauge.
Kill Switch: Test continuity; replace if faulty.
Flywheel: Check key for shearing; ensure tight mounting.
Testing: Use spark tester; should jump 1/4" gap.

CAUTION! Never crank engine with spark plug removed and wire grounded to cylinder.

Fuel System

Clean fuel system is essential for reliable operation.

Fuel Filter: Replace annually; located inside fuel tank.
Fuel Lines: Inspect for cracks; replace if hardened or leaking.
Fuel Mix: Use 50:1 ratio with 89+ octane gasoline and JASO FD certified 2-stroke oil.
Carburetor Diaphragms: Check for stiffness or tears; replace kit if needed.
Vent: Ensure fuel tank vent is clear.

Tip: Use ethanol-free fuel to prevent carburetor issues.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Won't start	No spark, flooded, fuel issue	Check spark, dry plug, clean carburetor, fresh fuel.
Starts then dies	Clogged fuel filter, vent, carb	Replace fuel filter, clear vent, clean carburetor.
Lacks power	Clogged air filter, exhaust, carb	Clean air filter, decarbonize exhaust, adjust carb.
Chain won't turn	Clutch, sprocket, brake	Inspect clutch springs, sprocket, disengage brake.
Overheating	Dull chain, lean mix, clogged fins	Sharpen chain, enrich mixture, clean cooling fins.
Oil not pumping	Clogged oiler, line, pump	Clean oil ports, replace line, check oil pump.
Excessive vibration	Loose parts, bent crankshaft	Tighten mounts, check crankshaft alignment.
Chain throws	Loose chain, worn bar, damaged drive links	Adjust tension, replace bar, inspect chain.

Reset: For electronic issues, disconnect spark plug wire for 30 seconds.

Parts Diagram

Refer to official Wildcat parts diagram (PN: WC38-2025) for exploded view and part numbers. Key assemblies:

Cylinder & Piston Assembly
Crankcase & Crankshaft
Carburetor & Air Filter
Clutch & Sprocket
Chain Brake Assembly
Ignition System
Fuel Tank & Handle
Guide Bar & Chain

Note: Always use part numbers when ordering replacements.

Warranty Information

Wildcat 38cc comes with 2-year limited warranty for residential use, 90 days commercial. Warranty covers defects in materials/workmanship. Not covered: normal wear, misuse, improper maintenance, non-genuine parts. Keep purchase receipt for warranty claims.

Service: 1-800-WILDCAT; www.wildcatchainsaws.com