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MTD 678 lawn tractor

MTD 678 lawn tractor Parts

Here are the diagrams and repair parts for MTD 678 lawn tractor, as well as links to manuals and error code tables, if available.

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Browse Parts for 678 Riding Mowers & Tractors

  • Hood Brkt. Support for MTD 678 - Part 783-0553

    Grille/ hood and fender diagram

    Hood Brkt. Support

    Part #783-0553

    The manufacturer no longer makes this part, and there's no substitute part

  • Extension Spring for MTD 678 - Part 732-0413

    Drive diagram

    Extension Spring

    Part #732-0413

    The manufacturer no longer makes this part, and there's no substitute part

  • Battery-275 for MTD 678 - Part 725-1707C

    Seat and main frame diagram

    Battery-275

    Part #725-1707C

    The manufacturer no longer makes this part, and there's no substitute part

  • Bracket Stabilizer for MTD 678 - Part 17636C

    Lift diagram

    Bracket Stabilizer

    Part #17636C

    The manufacturer no longer makes this part, and there's no substitute part

  • Handle Grip for MTD 678 - Part 720-0233

    Lift diagram

    Handle Grip

    Part #720-0233

    The manufacturer no longer makes this part, and there's no substitute part

  • Lawn & Garden Equipment Bearing for MTD 678 - Part 741-0419

    Drive diagram

    Lawn & Garden Equipment Bearing

    Part #741-0419

    The manufacturer no longer makes this part, and there's no substitute part

  • Bell Washer for MTD 678 - Part 736-0427

    Drive diagram

    Bell Washer

    Part #736-0427

    The manufacturer no longer makes this part, and there's no substitute part

  • Cover Belt 3 for MTD 678 - Part 783-0343A

    Deck "f" diagram

    Cover Belt 3

    Part #783-0343A

    The manufacturer no longer makes this part, and there's no substitute part

  • Lever Seat for MTD 678 - Part 783-0609

    Seat and main frame diagram

    Lever Seat

    Part #783-0609

    The manufacturer no longer makes this part, and there's no substitute part

  • Spoked Hub Cap (gray-opt.) for MTD 678 - Part 734-16134

    Steering diagram

    Spoked Hub Cap (gray-opt.)

    Part #734-16134

    The manufacturer no longer makes this part, and there's no substitute part

Most common symptoms to help you fix your riding mowers & tractors

Choose a symptom to see related riding mower and lawn tractor repairs.

Main causes: damaged tie rods, bent or worn wheel spindle, worn front axle, damaged sector gear assembly…

Main causes: dead battery, stale fuel, bad starter solenoid, ignition system problem, bad ignition interlock switch, clo…

Main causes: worn or broken blade belt, broken belt idler pulley, blade clutch cable failure, bad PTO switch, damaged ma…

Main causes: engine overfilled with oil, leaky head gasket or sump gasket, damaged carburetor seals, cracked fuel pump, …

Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…

Main causes: unlevel mower deck, dull or damaged cutting blades, worn mandrel pulleys, bent mower deck, engine needs tun…

Main causes: worn or broken ground drive belt, bad seat switch, transaxle freewheel control engaged, transaxle failure, …

Main causes: faulty battery, bad alternator…

Main causes: shift lever needs adjustment, neutral control needs adjustment…

Most common repair guides to help fix your riding mowers & tractors

These step-by-step repair guides will help you safely fix what’s broken on your riding mower or lawn tractor.

How to replace the starter solenoid on a riding lawn mower

How to replace the starter solenoid on a riding lawn mower

Replace the starter solenoid if it doesn't click when you turn the ignition key.…

Repair time and Difficulty

 30 minutes or less
How to replace a riding lawn mower ignition coil

How to replace a riding lawn mower ignition coil

If you're not getting spark from a good spark plug, the problem could be the ignition coil. Follow these step-by-step in…

Repair time and Difficulty

 30 minutes or less
How to replace a riding lawn mower fuel filter

How to replace a riding lawn mower fuel filter

Help your mower run better by replacing the fuel filter during your riding mower's annual tune-up.…

Repair time and Difficulty

 15 minutes or less

Effective articles & videos to help repair your riding mowers & tractors

Use the advice and tips in these articles and videos to get the most out of your riding mower or lawn tractor.

Top questions about Sears and Sears PartsDirect

Top questions about Sears and Sears PartsDirect

Get answers to frequently asked questions about Sears and Sears PartsDirect.…

Wiring schematic symbols explained video

Wiring schematic symbols explained video

Learn some of the most common symbols found in a wiring diagram and what they mean.…

Jump-starting a riding lawn mower battery video

Jump-starting a riding lawn mower battery video

Learn how to connect cables safely to jump-start your mower’s battery.…

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