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MTD
Front-Engine Lawn Tractor

Model # 688 Official MTD lawn tractor

Here are the diagrams and repair parts for Official MTD 688 lawn tractor, as well as links to manuals and error code tables, if available.

There are a couple of ways to find the part or diagram you need:

  • Click a diagram to see the parts shown on that diagram.
  • In the search box below, enter all or part of the part number or the part’s name.

Not all parts are shown on the diagrams—those parts are labeled NI, for “not illustrated”.

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For DIY troubleshooting advice and repair guides, visit our repair help section.

Owner’s manual

Model diagram and schematic

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ALL PARTS
Showing 10 of 397 parts  |
Lawn Mower Blade 742-0616A
#8A

Spindle assembly diagram

Lawn mower blade

Part #742-0616A

Replaced by #942-0616A

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Manufacturer substitution
This part replaces 742-0616A. Substitute parts can look different from the original.
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Get free shipping with Automatic Reorder

$29.58
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17% OFF Phone Price : $35.58
In Stock
Gasket 721-0208
#27

Engine diagram

Gasket

Part #721-0208

Replaced by #692236

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Manufacturer substitution
This part replaces 721-0208. Substitute parts can look different from the original.
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$6.56
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Ace Lawn & Garden Equipment Self-tapping Bolt, 5/16-18 X 3/4-in (replaces 1724491, 1740496, 1909304, 910-1260a, Gw-7101260) 710-1260A
Ace lawn & garden equipment self-tapping bolt, 5/16-18 x 3/4-in (replaces 1724491, 1740496, 1909304, 910-1260a, gw-7101260)

Part #710-1260A

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This item is not returnable
$4.25
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Steering Shaft 738-0919
#24

Steering wheel diagram

Steering shaft

Part #738-0919

Replaced by #738-0919B

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Manufacturer substitution
This part replaces 738-0919. Substitute parts can look different from the original.
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$55.20
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10% OFF Phone Price : $61.20
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Lawn Tractor Screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599) 710-0599
Lawn tractor screw (replaces 01000628, 01000865, 1186307, 1186308, 791-180288, 791-683298, 910-0599)

Part #710-0599

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Yard Machines Lawn & Garden Equipment Bell Washer (replaces 936-0242) 736-0242
Yard machines lawn & garden equipment bell washer (replaces 936-0242)

Part #736-0242

This item is not returnable
$6.58
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In Stock
Lawn Tractor Hex Bolt (replaces 910-0427, 910-3144) 710-3144
#10

Blades diagram

Lawn tractor hex bolt (replaces 910-0427, 910-3144)

Part #710-3144

This item is not returnable
$5.64
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Sears Lawn Tractor Screw 710-0627
Sears lawn tractor screw

Part #710-0627

This item is not returnable
$6.47
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13% OFF Phone Price : $7.47
Back Order
Lock Washer 736-0119
#12

Engine diagram

Lock washer

Part #736-0119

Replaced by #936-0119

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Manufacturer substitution
This part replaces 736-0119. Substitute parts can look different from the original.
This item is not returnable
$6.05
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14% OFF Phone Price : $7.05
In Stock
Toro Lawn Tractor Socket Screw (replaces 710-1314) 710-1314A
#5

Engine diagram

Toro lawn tractor socket screw (replaces 710-1314)

Part #710-1314A

This item is not returnable
$5.68
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15% OFF Phone Price : $6.68
In Stock

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Main causes: dead battery, stale fuel, bad starter solenoid, ignition system problem, bad ignition interlock switch, clo...

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Main causes: damaged tie rods, bent or worn wheel spindle, worn front axle, damaged sector gear assembly...

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Main causes: faulty battery, bad alternator...

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Main causes: shift lever needs adjustment, neutral control needs adjustment...

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