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MTD
Riding Mowers & Tractors

Model # 13A878XS099 Official MTD lawn tractor

Here are the diagrams and repair parts for Official MTD 13A878XS099 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 456 parts  |
Lawn Tractor 42-in Deck Bagging Blade 942-04308
#30

Mower deck/spindle 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 Blade Drive Belt, 1/2 X 96-1/2-in 954-04060C
#37

Mower deck/spindle diagram

Lawn tractor blade drive belt, 1/2 x 96-1/2-in

Part #954-04060C

Replaced by #490-501-Y044

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Manufacturer substitution
This part replaces 954-04060C. Substitute parts can look different from the original.
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$43.08 | 
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Lawn Mower Cable 946-05124
#37

Battery/lift diagram

Lawn mower cable

Part #946-05124

Replaced by #946-05124A

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Manufacturer substitution
This part replaces 946-05124. 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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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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Lawn Tractor Ignition Key 625-04124
#33

Fuel tank/upper dash panel diagram

Lawn tractor ignition key

Part #625-04124

Replaced by #925-1745A

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Manufacturer substitution
This part replaces 625-04124. Substitute parts can look different from the original.
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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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Yard Machines Lawn & Garden Equipment Nut 712-04064
#20

Battery/lift diagram

Yard machines lawn & garden equipment nut

Part #712-04064

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$4.49 | 
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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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