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138-503-3 MTD Lawn Tractor - Overview
Models starting with 138-503-3
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- 138-503-301 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-304 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-307 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-308 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-371 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-372 (1988) MTD Lawn Tractor (Lawn Tractor)
- 138-503-382 (1988) MTD Lawn Tractor (Lawn Tractor)
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$32.55
In Stock
Lawn Mower Ground Drive Belt
Part #954-04032B
This genuine drive belt is an original replacement part sourced directly from the manufacturer and is commonly used in Craftsman lawn mowers and edgers. Made from flexible rubber, it transfers power from the engine to the pulley that drives the cutting blades. Over time, the belt may become brittle or cracked due to wear and exposure, req...Read moreuiring replacement to maintain optimal performance. Measuring 3L x 35.80 inches, this belt is sold individually. A wrench may be needed for installation, depending on your equipment model.
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$42.70
Special Order
Control Box-thrott
Part #831-0823A
The Throttle Box Assembly, or the Throttle Assembly, is a kit that includes the housing, handle, and hardware. It is black and constructed of steel and plastic. It can be installed onto the right hand upper handle, using a screwdriver and pliers, and is rated as Medium difficulty to install.
This kit contains the parts that control the ...Read moreamount of the air and fuel entering the engine. When the part breaks (likely due to fatigue) you will no longer be able to control the engine. If nothing happens when you move the handle, that means it has become disconnected. When the part is broken it must be replaced. Check your model number to ensure you are selecting the correct replacement part.
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$10.54
In Stock
Lawn Mower Plastic Flange Bearing
Part #741-0487C
Made of durable silver plastic, this Flange Bearing is an authentic manufacturer-source replacement part for hundreds of models of lawn and garden equipment. It is used to allow a shaft to connect while moving smoothly and freely and is sold individually.
When this part malfunctions, you may notice the shaft becomes very sloppy or comes...Read more disconnected. To complete this repair, you will need a screwdriver, a socket set, and pliers.
Customers rate this repair as Medium difficulty.
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$6.74
In Stock
Wsh, Bell., .34 x .872 x .06
Part #736-0242
Sourced directly from the original manufacturer, this Bell Washer is made of gold-colored metal and is sold individually, not as part of a kit or assembly. It is used to provide spacing between various part assemblies along a shaft.
If you hear a strange noise coming from the shaft area, or you notice the Washer is visibly worn or damag...Read moreed, it will need to be replaced. Refer to your owners manual to determine the exact location of this part.
Customers rate the difficulty of this repair as Medium.
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$10.54
In Stock
Lawn Mower Brake Puck
Part #917-0678
When the brakes are applied, this brake puck presses against the brake disc in your lawn equipment to help slow down or stop it. The brake puck is in the brake assembly, which might be located near the transmission or the wheels of your machine. If you notice that the machine takes longer to stop or that there is a loud scraping or grindi...Read moreng noise when you push down on the brake, your brake puck may have worn out. If it is not replaced, you risk losing braking power, which leads to equipment damage or accidents. Before any repairs, make sure that your machine is turned off and that the spark plug is disconnected. To dissemble the brake assembly and access the brake puck, use pliers or a wrench to remove any bolts or clips holding it in place. With a screwdriver, pry the brake puck out of your machine. Since this genuine OEM part is sold individually, determine the number of pucks your machine needs by consulting your user manual.
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$6.57
In Stock
Washer-lock 5/16
Part #936-0119
This Washer-Lock 5/16 is a silver, metal part that is sold individually and comes direct from the manufacturer. With a 5/16 Inch Interior Diameter and 1/2 Inch Outside Diameter, it is used to prevent the nut from backing off and becoming loose on the pulley shaft, and is attached to the drive belt pulley assembly. You will know if you nee...Read mored this because your owners manual will specify it, or the model number of your machine will correspond with this part. If the part is broken due to fatigue, the shafts will free spin when they should be locked together, and must be replaced.
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$49.44
In Stock
Lawn Mower Grease Benalene (8 Oz)
Part #737-0300A
This 8-oz multi-purpose grease is an OEM replacement lubricant formulated for use in gear cases, transmissions, and chain cases on outdoor power equipment. It helps reduce friction and wear in high-load moving parts, supporting smooth operation and extending component life. Supplied in a convenient tube for easy application, it is an idea...Read morel choice for routine maintenance when servicing gearboxes, transaxles, or drive components that require consistent, heavy-duty lubrication.
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$6.40
Special Order
Lawn Mower Air Valve
Part #934-0255
The air valve attaches to the wheel and is made of a durable material. This is a genuine MTD, Ryobi, Yard Machines, Bolens, Troy-Bilt, and Yard Man part sourced directly from the manufacturer for use in chippers, shredders, cultivators, edgers, lawn tractors, snowblowers, and trimmers. Keep in mind that this part is sold individually. Whe...Read moren replacing this item a set of pliers might be required during the installation process. It might wear out over time and will need replacing.
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$53.20
In Stock
Lawn Mower Belt
Part #954-05040
This ground drive belt is for lawn tractors.
The ground drive belt turns the transmission pulley to move the tractor.
$31.28
On Order
Control-throttle
Part #831-0796A
The Throttle Control Box is an assembly containing the housing, trigger and hardware. It is black, plastic, rated as easy to install and requires a socket or wrench set. This kit controls the speed of the engine, and if broken you will lose control of the engine. If broken, the part should be replaced.
$10.05
On Order
Bearing-flange
Part #941-0225
The Hex Flange bearing, .630 inches I.D. is an OEM part. Black in color and made of metal, it is sold individually. It is installed using a wrench or socket and its installation has been rated as Easy by consumers.
This part attaches on the worm gear shaft in the cute, and is used to secure the worm gear on the shaft. If broken, you wil...Read morel no longer to be able to control the chute (or you may only have partial control). This breakage can occur due to fatigue over time, and means the part must be replaced. Refer to your owners manual or model number to ensure you are purchasing the correct part.
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$6.83
In Stock
Key-hi-pro
Part #914-0161
This authentic OEM hi-pro key, also called a woodruff key or key stock, is a metal component found in your lawn equipment that connects rotating parts. It is 3/16 inch wide and 5/8 inch long. It fits into a specially-shaped slot on a shaft and prevents the parts from moving or slipping out of position while your machine is running. To fin...Read mored and replace a hi-pro key on your machine, check your user guide for instructions. When removing the hi-pro key, insert a flathead screwdriver or needle-nose pliers into its groove and pry it out of its slot. Please bear in mind that this hi-pro key is sold individually.
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