Torque Specs for the Bolt on the Electric Clutch on the John Deere GT235

Torque Basics

• Torque specifications describe the rotational force of an object or the rotational force required to move that object. An engine, for instance, exerts rotational force as its cam shaft spins, while a bolt requires a certain amount of rotational force to be removed. The standard unit of measure for torque is pound-feet, which describes the amount of force exerted in pounds for each foot of a lever used to generate or stop the force in question.

Bolt Torque

• Bolt torque is the rotational force used to put a bolt in place. It also describes the rotational force required to remove a bolt. For instance, assume you exert 10 pounds of pressure on a 3-foot-long wrench to tighten a bolt. Removing that bolt requires 30 pound-feet (10 pounds x 3 feet) of torque. You can generate this by exerting 30 pounds of force on a 1-foot lever, 15 pounds of force on a 2-foot lever. ATSM International, formerly the American Society for Testing and Materials, an organization that creates standards for the construction, manufacturing and transportation industries, provides guidelines for bolt torque specifications based on the material used to make the bolt.

John Deere Bolt Torque

• Bolt specifications on the electric clutch of a John Deere GT235 depend upon the type of bolt used with the clutch. For instance, according to a chart from John Deere, a lubricated Class 4.8, M6 bolt used with John Deere equipment has torque specs of 3.5 pound-feet lubricated and 4.6 pound-feet dry, while a Class 4.8 M16 bolt has torque specs of 200 pound-feet lubricated and 250 pound-feet dry. The full range of bolt torque specs for bolts used in John Deere equipment runs from 3.5 pound-feet to 3500 pound-feet.

Determing GT235 Bolt Types

• Use the identifying numbers on the head of the bolt and the shape of the head to determine the class and type of the bolt. You can find charts correlating identifying numbers to bolts through a number of websites, including John Deere. Determine the torque specs of that bolt using an ATSM bolt torque chart or a bolt chart provided by John Deere. Figure out the material of the bolt before using the chart, because charts exist for numerous types of bolt, based on their compositional material.

Methods of Calculating Bolt Torque

• Three primary methods exist for calculating torque on a bolt you need to remove. If you know the tool used to put the bolt in place, you can calculate the torque specs of the bolt based on this tool or assume that whoever put the bolt in place adhered to ASTM standards for bolt torque and base your torque spec measurement on this. You can also use an online bolt torque calculator to determine a basic measurement for the torque required for a specific bolt. Bolt calculators require information such as a bolt's type, size, thread size, material and applied load. Calculators may automatically fill in applied load for you or provide a table of values for you to choose from based on the specifics of your bolt.