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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

  • Oil Drain Cap for MTD 678 - Part 737-0143

    Oil Drain Cap

    Part #737-0143

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

  • Lawn Tractor Axle Weldment End Cap for MTD 678 - Part 731-1649

    Steering diagram

    Lawn Tractor Axle Weldment End Cap

    Part #731-1649

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

  • Belt Cover for MTD 678 - Part 783-0063A

    Deck "h" diagram

    Belt Cover

    Part #783-0063A

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

  • Retainer for MTD 678 - Part 17782

    Grille/ hood and fender diagram

    Retainer

    Part #17782

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

  • Kit-deck 42" for MTD 678 - Part 753-0698

    Deck "g" diagram

    Kit-deck 42"

    Part #753-0698

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

  • Nut Retainin for MTD 678 - Part 726-0293

    Grille/ hood and fender diagram

    Nut Retainin

    Part #726-0293

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

  • Kit-deck 38" for MTD 678 - Part 753-0694

    Deck "f" diagram

    Kit-deck 38"

    Part #753-0694

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

  • Unknown Brand Name #689 Lawn & Garden Equipment Hex Nut for MTD 678 - Part 712-0337

    Deck "h" diagram

    Unknown Brand Name #689 Lawn & Garden Equipment Hex Nut

    Part #712-0337

    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

  • Harness Assembly for MTD 678 - Part 629-0301B

    Harness Assembly

    Part #629-0301B

    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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