How would you measure the length of this 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? Do you measure the outside or insides conference of a multi red belt? If you were to talk to a belt engineer, he 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 length of the belt is part of number. For example, this Continental OETS Automotive Multi Rib V-belt has part number 4060805. The last three digits in the part 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. In this example, a 4060805 indicates the belt is a six rib belt. For V-belts, the first and second digits designate the top width. The third and fourth digits indicate the outside length in inches. The fifth digit is the remainder of the outside length that is less than an inch. For multi rib belts, the first digit represents the style of belt, which is a multi V-belt. The second and third digit designate the number of ribs. The fourth, fifth, and sixth digits indicate the length of the belt. And the seventh digit is the remainder of the length that is less than an inch. 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 multi V up to 115 inches and V-belts up to 112.5 inches. It has a continental part number 08000. The tool can also measure V-belts of various width 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 where the edge of the belt is in the slot you can determine 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. On the left is inches and on the right is millimeters.
Measuring a multi V-belt is very similar. Place the belt over the groove section of the head and pull it taut. Read the length measurement on the vertical scale. The inch measurement is on the left side of the scale and the metric measurement is on the right side of the scale. In this case, belt length shows 805 or 80.5 inches. 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. Also, the tensioner can be damaged. To avoid a costly mistake by selecting a belt that is the wrong size, using the Continental Insta-Find measuring gauge can give you extra peace of mind. The belt will fit the application. Thanks for watching. We’ll see you again.