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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

  • 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

  • Hose Clamp for MTD 678 - Part 729-0205

    Tecumseh diagram

    Hose Clamp

    Part #729-0205

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

  • Stop Bracket for MTD 678 - Part 783-0611

    Seat and main frame diagram

    Stop Bracket

    Part #783-0611

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

  • Spring for MTD 678 - Part 732-0723

    Deck "h" diagram

    Spring

    Part #732-0723

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

  • Seat for MTD 678 - Part 757-0363A

    Seat and main frame diagram

    Seat

    Part #757-0363A

    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

  • Foot Pad Rh for MTD 678 - Part 731-0910

    Seat and main frame diagram

    Foot Pad Rh

    Part #731-0910

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

  • Dash Panel for MTD 678 - Part 731-1852

    Grille/ hood and fender diagram

    Dash Panel

    Part #731-1852

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

  • Sems Nut for MTD 678 - Part 712-0265

    Sems Nut

    Part #712-0265

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

  • Screw for MTD 678 - Part 710-0195

    Drive diagram

    Screw

    Part #710-0195

    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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