Get free shipping on your order, with any water filter subscription. Find my filter

Open Hamburger Menu
Sears Parts Direct
Tips to find your model number
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.

By Schematic
By Part
SELECT DIAGRAM
?

This is the number corresponding to the part on the diagram / schematic

Browse Parts for 678 Riding Mowers & Tractors

  • Fuel Tank Assembly for MTD 678 - Part 751-0657

    Seat and main frame diagram

    Fuel Tank Assembly

    Part #751-0657

    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

  • Heat Duct for MTD 678 - Part 731-1917

    Grille/ hood and fender diagram

    Heat Duct

    Part #731-1917

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

  • Adapter Harness for MTD 678 - Part 629-0208

    Twin cylinder diagram

    Adapter Harness

    Part #629-0208

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

  • Hood Bracket for MTD 678 - Part 683-0168

    Grille/ hood and fender diagram

    Hood Bracket

    Part #683-0168

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

  • Compression for MTD 678 - Part 732-0499

    Seat and main frame diagram

    Compression

    Part #732-0499

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

  • Spacer for MTD 678 - Part 748-0347

    Seat and main frame diagram

    Spacer

    Part #748-0347

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

  • Brake Disc for MTD 678 - Part 783-0342

    Brake Disc

    Part #783-0342

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

  • Tape-2 Sided for MTD 678 - Part 722-3021

    Grille/ hood and fender diagram

    Tape-2 Sided

    Part #722-3021

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

  • Frame for MTD 678 - Part 783-0043

    Frame

    Part #783-0043

    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.…

Parts & More

Chainsaw
Dishwasher
Dryer
Electric Water Heater
Gas Cooktop
Gas Range
Gas Walk-Behind Mower
Line Trimmer
Others
Parts
Pressure Washer
Range
Range Hood
Refrigerator
Snowblower
Stand Mixer
Vacuum Cleaner
Walk-Behind Mower