Timing belt is an important part of engine valve system, which can ensure the accuracy of intake and exhaust time by connecting with crankshaft and a certain transmission ratio. When the engine is running, under the "timing" connection, the piston stroke (up and down movement), valve opening and closing (time) and ignition sequence (time) should always keep "synchronous" operation. Replace the crankshaft belt. When replacing the crankshaft pulley, replace the wheel first. Remove the right front wheel of the excavator. When removing the wheel, if the excavator is not supported, loosen the screw. It's easier to screw up, or it won't work. In order to ensure safety, do a good job in insurance work. The removed screws should be put in the box, which is convenient for installation and will not be missed.
