STIHL MM55 Tiller Parts Manual

The STIHL MM55 Tiller is a professional-grade, lightweight, and maneuverable 2-cycle engine-powered cultivator designed for residential and commercial gardening. This manual provides detailed parts identification, diagrams, ordering information, and maintenance guidance to ensure proper assembly, operation, and longevity of your STIHL MM55 Tiller. Below are key sections for parts overview, assembly, maintenance, troubleshooting, and ordering.

1. Parts Overview & Diagrams 2. Assembly Instructions 3. Maintenance Parts & Schedule 4. Specifications 5. Controls & Operation 6. Engine Components 7. Tine & Drive System 8. Safety Features 9. Care & Storage 10. Warranty Information 11. Troubleshooting & Parts Replacement

Parts Overview & Diagrams

Key components: 2-cycle STIHL engine, Handlebar assembly, Tine assembly, Drive system, Fuel tank, Air filter, Spark plug, Recoil starter.

Part NumberDescriptionDiagram Reference
1140 400 1201Engine Assembly (Complete)Fig. 1-A
1140 790 2000Handlebar with ControlsFig. 2-B
1140 850 0600Tine Set (4 Tines)Fig. 3-C
1140 141 0600Drive BeltFig. 4-D
1140 141 0500Clutch AssemblyFig. 4-E
1140 850 0700Tine ShaftFig. 3-F
1140 400 1300Fuel Tank AssemblyFig. 1-G
1140 140 2000Air Filter CoverFig. 5-H
0000 350 2005Spark Plug (Bosch WSR6F)Fig. 1-I
1140 850 0800Recoil Starter AssemblyFig. 1-J

Assembly Instructions

Unpack and inspect all parts against packing list. Assemble on a clean, flat surface.

  1. Attach Handlebar: Align handlebar with mounting brackets on engine housing. Secure with provided bolts (Part #1140 792 1800).
  2. Install Tines: Slide tine set onto tine shaft. Secure with locking pin (Part #1140 850 0900).
  3. Connect Controls: Route throttle cable and clutch lever to handlebar. Adjust for smooth operation.
  4. Add Fuel & Oil: Fill fuel tank with 50:1 gasoline/oil mixture. Check oil level in gearbox.

WARNING! Wear protective gloves during assembly. Ensure all fasteners are tightened to specified torque.

Maintenance Parts & Schedule

Regular maintenance ensures optimal performance and extends tiller life.

  1. Air Filter: Clean every 10 hours; replace annually (Part #1140 140 2100).
  2. Spark Plug: Inspect every 25 hours; replace as needed (Part #0000 350 2005).
  3. Fuel Filter: Replace every season (Part #1140 357 0700).
  4. Drive Belt: Inspect for wear every 50 hours; replace if cracked (Part #1140 141 0600).
  5. Tines: Sharpen or replace when worn (Part #1140 850 0600).

CAUTION! Disconnect spark plug wire before performing maintenance.

Specifications

Controls & Operation

Handlebar Controls: Throttle lever, Clutch lever, Stop switch. Engine Controls: Choke, Primer bulb, Recoil starter.

Starting Procedure: Set choke, press primer 5x, pull recoil starter. Operation: Engage clutch lever to activate tines. Use throttle to control speed. Stopping: Release clutch, move throttle to idle, press stop switch.

Adjustments: Handlebar height, Tine depth, Throttle cable tension.

Engine Components

Key engine parts: Cylinder, Piston, Carburetor, Muffler, Ignition coil.

  1. Remove engine cover to access components.
  2. Refer to Fig. 1 for part locations and numbers.
  3. Use genuine STIHL parts for replacements.

Tip: Clean cooling fins regularly to prevent overheating.

Tine & Drive System

Supports forward tilling; tines rotate counter-clockwise.

  1. Tine Removal: Remove locking pin, slide tines off shaft.
  2. Belt Replacement: Remove cover, release tension, replace belt.
  3. Clutch Adjustment: Adjust cable for proper engagement.
  4. Shaft Inspection: Check for bends or wear annually.

WARNING! Ensure engine is off and cool before servicing drive system.

Safety Features

Safety Lever: Must be engaged for clutch to operate. Stop Switch: Cuts ignition instantly. Throttle Lockout: Prevents accidental acceleration. Protective Guards: Shield around tines and drive belt.

Care & Storage

Clean after each use. Store in dry place. For long-term storage: Drain fuel, run engine dry, remove spark plug and add oil to cylinder.

CAUTION! Never store with fuel in tank for more than 30 days.

Warranty Information

STIHL Limited Warranty: 2 years for residential use, 1 year for commercial use. Warranty covers defects in materials/workmanship. Does not cover normal wear, misuse, or non-STIHL parts. For warranty service, contact authorized STIHL dealer with proof of purchase. For support, visit www.stihlusa.com or contact 1-800-467-8445.

Troubleshooting & Parts Replacement

SymptomPossible CauseCorrective Action / Part Needed
Engine won't startFuel, spark, airCheck fuel mixture; replace spark plug (0000 350 2005); clean air filter (1140 140 2100).
Loss of powerClogged filter, carburetorClean/replace air filter; service carburetor (1140 120 0600 kit).
Tines not turningBelt, clutchInspect/replace drive belt (1140 141 0600); adjust clutch cable.
Excessive vibrationLoose tines, bent shaftTighten tine locking pin; inspect/replace tine shaft (1140 850 0700).
Oil leak from gearboxSeal, gasketReplace output shaft seal (1140 141 0800) or gearbox gasket (1140 141 0900).

Dealer Service: For complex repairs, visit authorized STIHL dealer.

Parts Ordering: Use part numbers above. www.stihlusa.com; 1-800-467-8445

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