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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.

MTD 678 lawn tractor
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Browse Parts for 678 Riding Mowers & Tractors

  • Adjustment Ferrule for MTD 678 - Part 711-0723A

    Lift diagram

    Adjustment Ferrule

    Part #711-0723A

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

  • Spacer Seat for MTD 678 - Part 731-1924

    Seat and main frame diagram

    Spacer Seat

    Part #731-1924

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

  • Brkt-l.h. for MTD 678 - Part 17669

    Drive diagram

    Brkt-l.h.

    Part #17669

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

  • Adjuster Link for MTD 678 - Part 711-0841

    Lift diagram

    Adjuster Link

    Part #711-0841

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

  • Choke Control for MTD 678 - Part 746-0720

    Grille/ hood and fender diagram

    Choke Control

    Part #746-0720

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

  • Bracket Assembly for MTD 678 - Part 16554A

    Drive diagram

    Bracket Assembly

    Part #16554A

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

  • Adapter Harness for MTD 678 - Part 629-0125

    Twin cylinder diagram

    Adapter Harness

    Part #629-0125

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

  • Hitch Plate for MTD 678 - Part 483-0355A

    Seat and main frame diagram

    Hitch Plate

    Part #483-0355A

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

  • Harness Assembly for MTD 678 - Part 629-0132

    Kohler diagram

    Harness Assembly

    Part #629-0132

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

  • Connecting Rod for MTD 678 - Part 783-0103

    Lift diagram

    Connecting Rod

    Part #783-0103

    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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