John Deere X350 Belt Diagram (2024)

FAQs

Why does my John Deere deck belt keep breaking? ›

A common cause of belt breakage is excessive grass clippings on the deck. Grass clippings can work their way under pulleys and deck covers, causing series problems. Make sure to clean off your deck after every mower use and follow manufacturer recommendations.

The belt tension is set with a spring and an eyebolt. Tighten or shorten the eyebolt to increase belt tension or loosen or lengthen the bolt to relieve tension. The correct tension is achieved when pressure is applied to the center of the longest run and belt is able to be pressed in about ½” from static position.

The cost of a new lawn mower belt will vary depending on the make and model of your mower and the type of belt needed. On average, a new belt can cost between $10 and $30. However, some high-end belts can cost up to $50 or more.

The deck belt is the one that powers the blades and the drive belt powers the tractor's motion. The deck belt comes with the deck when you remove the deck but the drive belt remains with the tractor.

The biggest cause of belts flying off of a mower deck is that the customer does not know that you MUST engage the mower with the engine running at FULL THROTTLE. Engaging the mower at anything less than full throttle can throw the belt off. The next thing that will cause this is an IDLER pulley beating that is dry.

Adjust the Grip

If you have the right belt and it's seemingly in good shape, the belt may be slipping because of incorrect belt tension. If the tension is too loose, then there won't be enough grip between the belt and the pulley to keep it on track.

The first potential culprit of your mower belt repeatedly breaking could be faulty bearings on your spindle or pulley. These components rotate at high speeds during operation, leading to intense heat that can potentially damage the bearings if not properly maintained.

Belts may be stored up to six years if properly stored at temperatures less than 85°F and relative humidity less than 70%. For every 15°F increase in storage temperature above 85°F, the time the belt can be stored without reduced performance decreases by one-half.

The proper tension for operating a V-belt drive is the lowest tension at which the belts will not slip at peak load conditions. For applications without a variable frequency drive (VFD) or starter, and the motor is “ran across the line”, the tension must be able to handle the increased motor torque during startup.

If the belt is too loose, it may slip or squeal, reducing its ability to drive engine accessories and potentially causing damage to the belt and other components. If the belt is too tight, it can cause excessive wear on the belt, pulleys, and bearings, leading to premature failure of these components.

How many belts does a lawn mower have? ›

Lawn Tractors usually have, at minimum, two belts. One is the drive belt which moves the tractor forward and backwards. The second belt is called a deck belt. Many people get confused here because the drive belt drives the tractor and the deck belt drives the blades.

It may have just one long serpentine belt or it may have two or three accessory drive belts. That's in addition to a timing belt, if your car is equipped with one.

All John Deere equipment - except for machines classified as 'Lawn Tractors' or 'Lawn and Garden tractors' - have a seatbelt and ROPS (external or built into the cab). This includes compact utility tractors, Gators, combines, sprayers and everything in between.