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MTD
Front-Engine Lawn Tractor

Model # 663 Official MTD lawn tractor

Here are the diagrams and repair parts for Official MTD 663 lawn tractor, as well as links to manuals and error code tables, if available.

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  • 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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Owner’s manual

Model diagram and schematic

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ALL PARTS
Showing 10 of 714 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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$30.47 | 
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Lawn Tractor Blade 742-0616
#23

Deck "g" diagram

Lawn tractor blade

Part #742-0616

Replaced by #942-0616A

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Manufacturer substitution
This part replaces 742-0616. Substitute parts can look different from the original.
BEST SELLER

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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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$4.34 | 
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Hex Screw 710-1260
Hex screw

Part #710-1260

Replaced by #710-1260A

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Manufacturer substitution
This part replaces 710-1260. Substitute parts can look different from the original.
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$4.34 | 
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Steering Shaft 738-0919
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 | 
10% OFF Phone Price : $61.20
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Yard-man Lawn & Garden Equipment Hex Patch Bolt (replaces 910-1309) 710-1309
Yard-man lawn & garden equipment hex patch bolt (replaces 910-1309)

Part #710-1309

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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

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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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In Stock
Bar Pivot Assembly 683-0128
#25

Steering diagram

Bar pivot assembly

Part #683-0128

Replaced by #683-0128B-0637

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Manufacturer substitution
This part replaces 683-0128. Substitute parts can look different from the original.
$90.71 | 
6% OFF Phone Price : $96.71
In Stock

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Why won't my riding mower cut grass?

Main causes: worn or broken blade belt, broken belt idler pulley, blade clutch cable failure, bad PTO switch, damaged ma…

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Main causes: faulty battery, bad alternator…

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Main causes: punctured tire or inner tube, leaky valve stem, damaged wheel rim…

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Why won't my riding mower start?

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

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Why is the steering loose on my riding mower?

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

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Why does my riding mower creep in neutral?

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

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Why does my riding mower run rough or misfire?

Main causes: clogged carburetor, damaged flywheel key, dirty spark plug, stale fuel, improper valve lash, engine needs a…

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Why won't my riding mower move?

Main causes: worn or broken ground drive belt, bad seat switch, transaxle freewheel control engaged, transaxle failure, …

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Why is my riding mower not cutting evenly?

Main causes: unlevel mower deck, dull or damaged cutting blades, worn mandrel pulleys, bent mower deck, engine needs tun…

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How to replace a mandrel assembly on a riding lawn mower

Replace the mandrel assembly if the blade shaft vibrates or doesn't spin.…

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Time required
 30 minutes or less
How to replace the flywheel key on a riding lawn mower

How to replace the flywheel key on a riding lawn mower

If the engine won't restart after hitting a stump or rock, the problem could be a sheared flywheel key. Follow these ste…

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Repair difficulty
Time required
 60 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…

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Repair difficulty
Time required
 30 minutes or less

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Riding lawn mower engine clicks but doesn't turn over video

Riding lawn mower engine clicks but doesn't turn over video

Check the starter solenoid, starter motor, wiring, battery and engine.…

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