Importance of Belt Measuring Tools

How would you measure the length of a belt that does not have the part number on it? Would you measure the inside with the ribs or the backing of the belt? Should it be measured on or off the pulleys? What would you use to measure the length of the pulley? A string, ruler, tape measure?

If you were to talk to a belt engineer, they would tell you that they call the measurement the effective length, and it is measured at the cord line. If you talk to a catalog specialist at a belt company, they would tell you the effect of the length of the belt is part of a number. For example, the Continental OETS Automotive Multi Rib V-belt has part number 4060805. The last three digits of that number indicate the belt has a length of 80.5 inches.

The other digits in this Continental part number for multi-rib belts can be translated into dimensions and features of the belt. Now that we know the correct length of a belt, what is the correct tool to measure the effective belt length at the cord line? The answer is the Continental Insta-Find measuring gauge.

It can quickly determine the effective length of a multi-rib V-belt up to 115 inches and regular V-belts up to 112.5 inches. It has a Continental part number 08000 and can also measure V-belts of various widths for standard and metric sizes. For multi-rib belts, it can measure a belt as small as three grooves and as large as 12.

To measure V-belts, place the belt in the V-belt groove and pull the belt taut with a movable head. Look at the gauging slots. By looking at where the edge of the belt is in the slot, you can determine the width of the belt in inches or millimeters. Using the width measurement from the gauging slots, look at the vertical scale below to determine the length by matching it to the width measurement on the scale.

Measuring a multi-V-belt is very similar. Why is belt length important? Simply put the wrong effective length can damage all the components of the accessory drive belt system. If a belt is too long, it can cause noise, premature wear, damage to the tensioner and loss of power steering assist because the belt is too loose. If a belt is too short, it can also cause premature wear to the belt and components on the belt drive system, including the alternator, power steering pump, water pump and AC compressor. The tensioner can also be damaged. To avoid a costly mistake by selecting a belt that is the wrong size, use the Continental Insta-Find measuring gauge to give you extra peace of mind. With this tool, you’ll find a belt that will fit the application.

This video is sponsored by Continental.