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MTD
Front-Engine Lawn Tractor

Model # 13BJ78SS099 Official MTD tractor

Here are the diagrams and repair parts for Official MTD 13BJ78SS099 tractor, as well as links to manuals and error code tables, if available.

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Owner’s manual
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Model diagram and schematic

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Showing 10 of 480 parts  |
Lawn Tractor 42-in Deck Bagging Blade 942-04308
#39

Mower deck/spindle pulley diagram

Lawn tractor 42-in deck bagging blade

Part #942-04308

Replaced by #942-04308A

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Manufacturer substitution
This part replaces 942-04308. Substitute parts can look different from the original.
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Lawn Tractor Ground Drive Belt, 2/3 X 90-4/5-in (replaces 754-0467a, 954-0467) 954-0467A
#69

Transmission diagram

Lawn tractor ground drive belt, 2/3 x 90-4/5-in (replaces 754-0467a, 954-0467)

Part #954-0467A

Replaced by #490-501-Y035

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Manufacturer substitution
This part replaces 954-0467A. Substitute parts can look different from the original.
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Lawn Tractor Blade Engagement Cable (replaces 746-04173e, 946-04173d) 946-04173E
#22

Battery/frame diagram

Lawn tractor blade engagement cable (replaces 746-04173e, 946-04173d)

Part #946-04173E

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Yard Machines Lawn & Garden Equipment Lock Nut, 5/16-18 (replaces 753-05591) 712-04063
Yard machines lawn & garden equipment lock nut, 5/16-18 (replaces 753-05591)

Part #712-04063

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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
#4

Transmission diagram

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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Yard Machines Lawn & Garden Equipment Nut 712-04064
Yard machines lawn & garden equipment nut

Part #712-04064

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Lawn Tractor Gauge Wheel 734-04155
#26

Mower deck/spindle pulley diagram

Lawn tractor gauge wheel

Part #734-04155

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Lawn Tractor Mandrel Assembly 918-04822A
#1

Mower deck/spindle pulley diagram

Lawn tractor mandrel assembly

Part #918-04822A

Replaced by #918-04822B

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Manufacturer substitution
This part replaces 918-04822A. Substitute parts can look different from the original.
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Yard Machines Lawn Tractor Flange Nut (replaces 00012173, Wd-129-103) 712-04065
Yard machines lawn tractor flange nut (replaces 00012173, wd-129-103)

Part #712-04065

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Lawn Tractor Steering Shaft 738-0919A
#15

Steering diagram

Lawn tractor steering shaft

Part #738-0919A

Replaced by #738-0919B

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This part replaces 738-0919A. Substitute parts can look different from the original.
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