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MTD
Front-Engine Lawn Tractor

Model # 13BL78XT099 Official MTD lawn tractor

Here are the diagrams and repair parts for Official MTD 13BL78XT099 lawn 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 541 parts  |
Lawn Tractor Blade Drive Belt, 1/2 X 103-1/16-in 954-04219
#51

Deck/spindle pulley diagram

Lawn tractor blade drive belt, 1/2 x 103-1/16-in

Part #954-04219

Replaced by #490-501-M009

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Manufacturer substitution
This part replaces 954-04219. Substitute parts can look different from the original.
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Troybilt Lawn Tractor Blade Engagement Cable (replaces 946-05124) 946-05124A
#22

Frame/battery/lift diagram

Troybilt lawn tractor blade engagement cable (replaces 946-05124)

Part #946-05124A

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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
#61

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 Transaxle Belt, 2/3 X 40-9/10-in 954-04208A
#60

Transmission diagram

Lawn tractor transaxle belt, 2/3 x 40-9/10-in

Part #954-04208A

Replaced by #490-501-Y007

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Manufacturer substitution
This part replaces 954-04208A. Substitute parts can look different from the original.
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Lawn & Garden Equipment Hex Flange Nut (replaces 753-05549, 912-0417a) 712-0417A
#20

Deck/spindle pulley 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/wheels diagram

Lawn tractor bearing (replaces 741-04124)

Part #941-04124

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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 Gauge Wheel 734-04155
#31

Deck/spindle pulley diagram

Lawn tractor gauge wheel

Part #734-04155

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