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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

  • Steering Cap for MTD 678 - Part 731-1460

    Steering diagram

    Steering Cap

    Part #731-1460

    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

  • Board-runnin for MTD 678 - Part 17770C

    Seat and main frame diagram

    Board-runnin

    Part #17770C

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

  • Speed Selector for MTD 678 - Part 16192A

    7 speed selector diagram

    Speed Selector

    Part #16192A

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

  • Oil Drain Pipe for MTD 678 - Part 737-0286

    Tecumseh diagram

    Oil Drain Pipe

    Part #737-0286

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

  • Selector Seal for MTD 678 - Part 783-0610

    Seat and main frame diagram

    Selector Seal

    Part #783-0610

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

  • Pivot Bracket for MTD 678 - Part 783-0041B

    Steering diagram

    Pivot Bracket

    Part #783-0041B

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

  • Deck Ass'y-2 for MTD 678 - Part 16998A

    Grille/ hood and fender diagram

    Deck Ass'y-2

    Part #16998A

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

  • Height Adjustment Stop for MTD 678 - Part 683-0003

    Lift diagram

    Height Adjustment Stop

    Part #683-0003

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

  • Exhaust Pipe for MTD 678 - Part 751-0621

    Kohler diagram

    Exhaust Pipe

    Part #751-0621

    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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