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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 & 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 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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Exhaust Gasket BS-692236
#7

31p677-0912-g5 engine diagram

Exhaust gasket

Part #BS-692236

Replaced by #692236

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Manufacturer substitution
This part replaces BS-692236. Substitute parts can look different from the original.
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$6.76 | 
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Lawn & Garden Equipment Hex Flange Nut (replaces 753-05549, 912-0417a) 712-0417A
#17

Mower deck/spindle pulley diagram

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

Part #712-0417A

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$8.00 | 
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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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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 Mower Idler Pulley 753-08068
#48

Mower deck/spindle pulley diagram

Lawn mower idler pulley

Part #753-08068

Replaced by #753-08171

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Manufacturer substitution
This part replaces 753-08068. Substitute parts can look different from the original.
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$34.29 | 
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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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Lawn Tractor Wheel Cap (replaces 731-0484a) 931-0484A
#12

Steering diagram

Lawn tractor wheel cap (replaces 731-0484a)

Part #931-0484A

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