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Home Workshop: Honda drive belt check

CHECKING

Remove any body panels necessary to access the transmission cover on the left-hand side of the engine. You may need to remove the air filter housing and detach the rear brake cable.

Undo the transmission cover bolts and remove the cover (see image 1). If it won’t lift away easily, tap it gently around the edge with a soft-faced hammer. Remove the gasket. If damaged, discard it and fit a new one on reassembly.

Twist & GoNote the location of the dowels and remove them for safekeeping if they are loose.

Clean any dust or dirt from the inside of the casing with a suitable solvent, taking care to avoid contact with the belt and the drive faces of the pulleys. Any evidence of oil inside the casing suggests a worn seal either on the crankshaft or the gearbox input shaft, which must be rectified. Evidence of grease inside the casing suggests worn seals in the clutch centre which should also be rectified.

Check along the entire length of the belt for cracks, splits, frays and damaged teeth and replace the belt with a new one if any damage is found (see image 2).

The edges of the belt will gradually wear away (black dust inside the casing is evidence of belt wear). If you have a wear limit for the drive belt, measure the width of its outer face. If the drive belt has worn below the limit, or if the belt shows signs of fraying or cracking, or if it is contaminated with oil or grease, or at the specified interval regardless of condition, it must be renewed.

Note: If there is any doubt about the condition of the drive belt, replace it with a new one just in case – a broken belt could cause severe damage to engine or gearbox components.

CHANGING

To change the belt you need to remove the drive pulley outer half (see image 3). In order to slacken the drive pulley nut, the pulley must be held to prevent it turning. Most manufacturers produce a service tool which locates in the holes in the outer face, although a tool can easily be made from two strips of steel which will hold the pulley in a similar way. In all cases make sure the tool is securely located and won’t slip.

With the pulley held, unscrew the nut and remove the washer. Slide the outer half of the drive pulley off the shaft, then slip the old belt out of the driven pulley and remove it.

Fit the new belt, making sure any directional arrows point in the direction of normal rotation (see image 4). Ease the belt into the driven pulley to ensure there is sufficient slack to avoid the belt being trapped when the outer half of the drive pulley is installed. If necessary, grasp the driven pulley and pull it towards the clutch to compress the spring and press the drive belt into the pulley to create slack at the front to ease fitting of the drive pulley.

Twist & GoSlide the outer half of the drive pulley onto the crankshaft. Lubricate the nut threads and inner seating face with clean oil. Fit the washer and tighten the nut finger-tight. Make sure the outer pulley half butts against the centre sleeve and is not skewed by the drive belt. Use the method employed on removal to prevent the pulley turning and tighten the nut. Ease the drive belt out of the driven pulley to reduce the slack in the belt. Clean any dust from inside the casing before installing the drive belt cover.