Genuine Volvo S80 Timing Belt

Volvo S80 Timing Belt Parts and Q&A

• Timing Belt
  30731727
  Q: What is the importance of maintaining correct phasing between the camshaft and crankshaft during timing belt replacement for diesel engines on Volvo S80?

  A:

  The Camshaft and coolant pump sprockets are controlled by the timing belt from the crankshaft sprocket, ensuring the correct valve timing, any slip or break in the timing belt can cause serious engine damage when there is piston to valve contact. It is extremely important to keep the correct phasing of camshaft to crankshaft correct while the timing belt is off, this is done by setting the engine to Top Dead Centre (TDC) before removal and not until the belt is refitted to avoid rotating the shafts. TDC is the maximum position that the piston attains in its cylinder usually corresponding with No 1 cylinder on the compression stroke. Before starting work, disconnect the battery and then loosen the right-hand front road wheel bolts, jack the vehicle up and remove the roadwheel. Access the crankshaft pulley by removing a metal protection plate, and by folding the wheel arch liner. Loosen the servo hose cable tie, remove the engine cross-stay and remove timing belt outer cover. Move the power steering fluid reservoir out of the way but do not disconnect hoses, remove the auxiliary drivebelt and remove the timing belt lower cover. Turning the crankshaft clockwise and aligning the markings on the camshaft sprocket and timing belt rear cover, removing the crankshaft pulley, taking care not to rotate the crankshaft. Check alignment of the marks and adjust if necessary, slacken the timing belt tensioner and set into position before removing the timing belt without turning the shafts. Inspect the belt for contamination and wear and replace if needed and check the tensioner and idler pulleys for noise. For refitting, make sure the crankshaft and camshaft are aligned, fit the new belt around the right sprockets, and make sure the front run is taut. Adjust the tensioner roller and check the movement of the tensioner arm, and turn the crankshaft two full turns to check alignment of the timing marks and the tensioner indicator position.
• Timing Belt
  31104600
  Q: How to remove and replace the timing belt for petrol engines on Volvo S80?

  A:

  To remove the timing belt start by disconnecting the battery negative lead and remove the engine compartment cross stay by undoing the bolts and nuts. Next, remove the auxiliary drivebelt, and remove the timing belt inner/upper cover by removing the Torx screws and spring clips. If it would work, unbolt the turbocharger intake ducting and remove the spark plug cover. Move the power steering fluid reservoir out of the way without disconnecting the hoses and make sure to keep it upright. Reach up and disconnect the coolant level sensor wiring by lifting the cooling system expansion tank out. Remove the timing belt front cover by undoing the bolt in the centre of the cover and lifting the cover to release the clips. Jack up the car at the front, remove the right hand roadwheel at the front and fold forward the inside of the wheel arch liner to get at the crankshaft pulley. Temporarily install the timing belt inner upper cover, and then turn the crankshaft in a clockwise direction until the timing marks are aligned. Remove the crankshaft pulley, which is held in place by four bolts and a central nut, using a home-made tool to hold it in place while you loosen the nut. For models up to 2006, use a 6 mm Allen key to loosen the timing belt tensioner and turn it to take tension off it. For models from 2006, you will need to slightly loosen the tensioner centre bolt and lock it in position. If reusing a belt, mark the running direction of the belt, and then slip the belt off of the sprockets and idler pulleys. Check the idler pulley for any roughness and check the timing belt for wear or any damage and renew if required. If you have over 36,000 miles on the existing belt, replace it regardless of its condition. Check for oil or coolant leaks, and check for failure of the coolant pump. Renew the tensioner assembly if there is any doubt about the condition of the item. Before refitting the timing belt, make sure that the sprockets are in place. Refit the belt tensioner, making sure to place it in the proper position, and slip the belt over the crankshaft sprocket and other parts and hold it taut. Recheck the alignment of the sprocket marks then adjust the tensioner as required on models made up to 2006 or remove the locking pin on later models. Once you have made sure that you can align the timing marks again, refit the crankshaft pulley and have all bolts tightened to specified torque. Finally, secure the wheel arch liner, refit the roadwheel and bring the car down, tightening the wheel bolts in a diagonal order before fitting all other components removed to get at them.