The correct installation and adjustment of the camshaft drive belt/timing belt is mandatory if the engine is to run properly. The camshaft controls the opening of the camshaft and the crankshaft. When any given piston is on the intake stroke the corresponding intake valve must be open to admit air/fuel mixture into the cylinder. When the same piston is on the compression and power strokes, both valves in that cylinder must be closed. When the piston is on the exhaust stroke, the exhaust valve for that cylinder must be open. If the opening and closing of the valves is not coordinated with the movements of the pistons, the engine will run very poorly, if at all.
The camshaft drive belt/timing belt also turns the engine auxiliary shaft. The distributor is driven by the engine auxiliary shaft. Since the distributor controls ignition timing, the auxiliary shaft must be coordinated with the camshaft and the crankshaft, since both valves in any given cylinder must be closed and the piston in that cylinder near the top of the compression stroke when the spark plug fires.
Due to this complex interrelationship between the camshaft, the crankshaft and the auxiliary shaft, the cogged pulleys on each component must be aligned when the camshaft drive belt/timing belt is installed.
REMOVAL & INSTALLATION
2.0L and 2.3L Gasoline Engines
See Figures 1, 2 and 3
- Rotate the engine so that No. 1 cylinder is at TDC on the compression stroke. Check that the timing marks are aligned on the camshaft and crankshaft pulleys. An access plug is provided in the cam belt cover so that the camshaft timing can be checked without removal of the cover or any other parts. Set the crankshaft to TDC by aligning the timing mark on the crank pulley with the TDC mark on the belt cover. Look through the access hole in the belt cover to make sure that the timing mark on the cam drive sprocket is lined up with the pointer on the inner belt cover.
Always turn the engine in the normal direction of rotation. Backward rotation may cause the timing belt to jump time, due to the arrangement of the belt tensioner.
- Drain cooling system. Remove the upper radiator hose as necessary. Remove the fan blade and water pump pulley bolts.
- Loosen the alternator retaining bolts and remove the drive belt from the pulleys. Remove the water pump pulley.
- Loosen and position the power steering pump mounting bracket and position it aside.
- Remove the four timing belt outer cover retaining bolts and remove the cover. Remove the crankshaft pulley and belt guide.
- Loosen the belt tensioner pulley assembly, then position a camshaft belt adjuster tool (T74P-6254-A or equivalent) on the tension spring rollpin and retract the belt tensioner away from the timing belt. Tighten the adjustment bolt to lock the tensioner in the retracted position.
- Remove the timing belt.
- Install the new belt over the crankshaft sprocket and then counterclockwise over the auxiliary and camshaft sprockets, making sure the lugs on the belt properly engage the sprocket teeth on the pulleys. Be careful not to rotate the pulleys when installing the belt.
- Release the timing belt tensioner pulley, allowing the tensioner to take up the belt slack. If the spring does not have enough tension to move the roller against the belt (belt hangs loose), it might be necessary to manually push the roller against the belt and tighten the bolt.
The spring cannot be used to set belt tension; a wrench must be used on the tensioner assembly.
- Rotate the crankshaft two complete turns by hand (in the normal direction of rotation) to remove the slack from the belt, then tighten the tensioner adjustment and pivot bolts to specifications. Refer to the necessary illustrations. Make sure the belt is seated properly on the pulleys and that the timing marks are still in alignment when No. 1 cylinder is again at TDC/compression.
- Install the crankshaft pulley and belt guide.
- Install the timing belt cover.
- Install the water pump pulley and fan blades. Install upper radiator hose if necessary. Refill the cooling system.
- Position the alternator and drive belts, then adjust and tighten it to specifications.
- Start the engine and check the ignition timing. Adjust the timing, if necessary.
See Figures 4, 5, 6, 7, 8, 9 and 10
- Disconnect battery ground cables from both batteries.
- Remove cooling fan and fan shroud.
- Remove accessory drive belts.
- Rotate crankshaft in direction of engine rotation to bring No. 1 piston to TDC of compression stroke.
- Remove crankshaft pulley.
- Remove upper and lower front covers.
- Loosen belt tensioners from timing belts. Remove belt(s), as necessary.
- Align crankshaft timing marks.
- Align LH and right hand silent shaft timing marks.
- Install silent shaft belt.
Install belt in original direction of rotation. For ease of installation, pry on tensioner spring to reduce load on tensioner.
- Align camshaft timing marks.
- Install injection pump/camshaft timing belt as follows.
To ease installation, locally manufacture the following tool. Using a pivot nut from a rear brake shoe adjuster, weld a piece of bar stock on the end.
- Using the tensioner spring tool, release the tension on the tension spring for the injection pump/camshaft timing belt.
- After releasing spring tension, rotate tensioner toward water pump and tighten top bolts.
- Install the belt.
- Adjust silent shaft belt and camshaft/injection pump belt tensions.
- Install upper and lower front timing covers.
- Install crankshaft pulley.
- Install accessory drive belts.
- Install cooling fan and fan shroud.
- Connect battery ground cables to both batteries.
- Remove timing belt upper cover.
- Rotate engine until No. 1 piston is at TDC on compression stroke.
- Ensure crankshaft pulley, injection pump sprocket and camshaft sprocket are aligned with their timing marks.
- Loosen top belt tensioner bolt one or two turns and loosen bottom bolt one complete turn. This allows tensioner spring to automatically adjust belt tension.
- Rotate crankshaft clockwise to that alignment pointer on timing cover aligns with second tooth from alignment mark on camshaft sprocket.
- Tighten top belt tensioner mounting bolt to specification, then tighten bottom bolt to specification.
- Rotate crankshaft counterclockwise until timing marks are aligned. Push belt down halfway between injection pump sprocket and camshaft sprocket and check deflection. If properly tensioned, belt should deflect 4-5mm.
- Rotate crankshaft until No. 1 piston is at TDC on compression stroke.
- Remove access cover for top belt tensioner bolt by inserting a suitable tool in slot shown and prying out.
- Loosen top belt tension mounting bolt one complete turn. Then, loosen bottom bolt one to two turns. This allows tensioner spring to automatically adjust belt tension.
- Tighten bottom tensioner bolt to specification, then tighten top bolt to specification.
- Install access cover for top tensioner bolt by sliding down along two guide lines embossed on front lower cover.