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MTD
Front-Engine Lawn Tractor

Model # 13AP78XS099 Official MTD tractor

Here are the diagrams and repair parts for Official MTD 13AP78XS099 tractor, as well as links to manuals and error code tables, if available.

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

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Owner’s manual
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Model diagram and schematic

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Showing 10 of 400 parts  |
Lawn & Garden Equipment Cotter Pin, 1/4- To 5/16-in 714-04040
Lawn & garden equipment cotter pin, 1/4- to 5/16-in

Part #714-04040

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Lawn Tractor 42-in Deck 3-in-1 Blade (replaces 742-0616a, 742-0616a-0637, 942-04126, 942-0616) 942-0616A
#NI

Deck/spindle assembly diagram

Lawn tractor 42-in deck 3-in-1 blade (replaces 742-0616a, 742-0616a-0637, 942-04126, 942-0616)

Part #942-0616A

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Lawn & Garden Equipment Hex Flange Nut (replaces 753-05549, 912-0417a) 712-0417A
#19

Deck/spindle assembly diagram

Lawn & garden equipment hex flange nut (replaces 753-05549, 912-0417a)

Part #712-0417A

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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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Lawn Tractor Bearing (replaces 741-04124) 941-04124
#16

Steering diagram

Lawn tractor bearing (replaces 741-04124)

Part #941-04124

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Lawn Tractor Steering Sector Gear 617-04094
#1

Steering diagram

Lawn tractor steering sector gear

Part #617-04094

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Troybilt Lawn Tractor Mandrel Assembly 918-06991
#1

Deck/spindle assembly diagram

Troybilt lawn tractor mandrel assembly

Part #918-06991

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Lawn Tractor Wheel Cap (replaces 731-0484a) 931-0484A
#13

Steering diagram

Lawn tractor wheel cap (replaces 731-0484a)

Part #931-0484A

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Lawn Tractor Interlock Switch 725-04363
Lawn tractor interlock switch

Part #725-04363

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Lawn Tractor Self-tapping Screw, 5/16-18 X 3/4-in (replaces 01008620) 710-04484
Lawn tractor self-tapping screw, 5/16-18 x 3/4-in (replaces 01008620)

Part #710-04484

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