GENERAL INFORMATION
Timing belts are typically only used on overhead camshaft engines. Timing belts are used to synchronize the crankshaft with the camshaft, similar to a timing chain on an overhead valve (pushrod) engine. Unlike a timing belt, a timing chain will normally last the life of the engine without needing service or replacement. Timing belts use raised teeth to mesh with sprockets to operate the valvetrain of an overhead camshaft engine.
Whenever a vehicle with an unknown service history comes into your repair facility or is recently purchased, here are some points that should be asked to help prevent costly engine damage:
Does the owner know if, or when the belt was replaced-If the vehicle purchased is used, or the condition and mileage of the last timing belt replacement are unknown, it is recommended to inspect, replace or at least inform the owner that the vehicle is equipped with a timing belt.Note the mileage of the vehicle. The average replacement interval for a timing belt is approximately 60,000 miles (96,000 km).
Interference Engines
Engines, chain-or belt-driven, can be classified as either free-running or interference, depending on what would happen if the piston-to-valve timing were disrupted. A free-running engine is designed with enough clearance between the pistons and valves to allow the crankshaft to rotate (pistons still moving) while the camshaft stays in one position (several valves fully open). If this condition occurs normally, no internal engine damage will result. In an interference engine, there is not enough clearance between the pistons and valves to allow the crankshaft to turn without the camshaft being in time.
An interference engine can suffer extensive internal damage if a timing belt fails. The piston design does not allow clearance for the valve to be fully open and the piston to be at the top of its stroke. If the belt fails, the piston will collide with the valve and will bend or break the valve, damage the piston, and/or bend a connecting rod. When this type of failure occurs, the engine will need to be replaced or disassembled for further internal inspection; either choice costing many times that of replacing the timing belt.
INSPECTION
All engines covered herein utilize timing belts to drive the camshaft from the crankshaft's turning motion and to maintain proper valve timing. Some manufacturer's schedule periodic timing belt replacement to assure optimum engine performance, to make sure the motorist is never stranded should the belt break (as the engine will stop instantly) and for some (manufacturer's with interference motors) to prevent the possibility of severe internal engine damage should the belt break.
Although the 1.5L and 1.8L engines are not listed as an interference motors (it is not listed by the manufacturer as a motor whose valves might contact the pistons if the camshaft was rotated separately from the crankshaft) the first 2 reasons for periodic replacement still apply and the timing belt should be replaced at 60,000 miles (96,000 km). The 1.6L, 2.0L, 2.4L, 3.0L, and 3.5L engines are listed as interference motors, so the timing belt MUST be replaced at 60,000 miles (96,000 km) to avoid severe engine damage if the belt should break.
But whether or not you decide to replace the timing belt in the manufacturers schedule, you would be wise to check it periodically to make sure it has not become damaged or worn. Generally speaking, a severely worn belt may cause engine performance to drop dramatically, but a damaged belt (which could give out suddenly) may not give as much warning. In general, any time the engine timing cover(s) is (are) removed you should inspect the belt for premature parting, severe cracks or missing teeth. Also, an access plug is provided in the upper portion of the timing cover so that camshaft timing can be checked without cover removal. If timing is found to be off, cover removal and further belt inspection or replacement is necessary.
REMOVAL & INSTALLATION
NOTE
The radio may have a coded theft protection circuit. Obtain the code before disconnecting the battery, removing the radio fuse, or removing the radio.
CAUTION
Timing belt maintenance is extremely important. All Hyundai models use interference-type non-freewheeling engines. Should the timing belt break in these engines, the valves in the cylinder head will come in contact with the pistons, causing major engine damage. The recommended replacement interval for timing belts is 60,000 miles.
CAUTION
On models with an air bag, wait at least 90 seconds from the time that the ignition switch is turned to the LOCK position and the battery is disconnected before performing any further work.
- Position the engine so the No. 1 cylinder is at Top Dead Center (TDC) of its compression stroke.
- Remove all necessary components for access to the timing belt covers, then remove the covers from the engine.
CAUTIONBe sure to disconnect the negative battery cable. Wait at least 90 seconds after the negative battery cable is disconnected to prevent possible deployment of the air bag. - If the same timing belt will be reused, mark the direction of the timing belt's rotation for installation in the same direction. Be sure the engine is positioned so the No. 1 cylinder is at the TDC of its compression stroke and the timing marks are aligned with the engine's timing mark indicators on the rear timing covers.
- Remove the timing belt.
WARNINGTurning the camshaft sprocket when the timing belt is removed could cause the valves to contact with the pistons, resulting in severe engine damage. - Remove the bolts that secure the auto-tensioner to the engine block and remove the tensioner.
To install:
NOTE
The auto-tensioner assembly must be reset to correctly adjust belt tension.
- Loosen the center bolt of tensioner pulley to provide timing belt slack. Remove the timing belt tensioner assembly.
- Position the auto-tensioner into a vise with soft jaws. The plug at the rear of tensioner protrudes, be sure to use a washer as a spacer to protect the plug from contacting vise jaws.
- Slowly push the rod into the tensioner until the set hole in rod is aligned with set hole in the auto-tensioner.
- Insert a 0.055 in. (1.4mm) wire into the aligned set holes. Unclamp the tensioner from the vise and install it on the engine. Tighten tensioner mounting bolts to 17 ft. lbs. (24 Nm).
WARNINGDO NOT rotate or turn the camshafts when removing the sprockets or severe engine damage will result from internal component interference. - Align the mark on the crankshaft sprocket with the mark on the front case. Then, move the crankshaft sprocket 3 teeth counterclockwise.
- Align the timing marks of the camshafts with the marks on the rear covers.
- Realign the crankshaft pulley with timing mark on the housing.
NOTEBe sure camshafts-to-cylinder heads and crankshaft-to-front cover timing marks are aligned. - Install the timing belt around the pulleys in the following order:
- Crankshaft pulley.
- Idler pulley.
- Left camshaft sprocket.
- Water pump pulley.
- Right camshaft sprocket.
- Tensioner pulley.
NOTESince the camshaft sprockets turn easily because of spring action, be careful not to get your fingers caught.
- Align all timing mark on the crankshaft and raise tensioner pulley against belt to remove slack, snug tensioner bolt.
- Check the alignment of all the timing.
- Using special tool MD998769, rotate the crankshaft 1 / 4 turn counterclockwise, then rotate the crankshaft clockwise to align the timing marks. Check that all the timing marks are in alignment.
- Loosen the center bolt on the tensioner pulley. Using tool MD998767 and a torque wrench, apply 3.3 ft. lbs. (4.4 Nm) to the tool on the tensioner. Tighten the tensioner bolt to 33 ft. lbs. (44 Nm) and be sure the tensioner does not rotate with the bolt.
- Rotate the crankshaft two complete turns clockwise and let it sit for approximately five minutes. Then, check that the set pin can easily be inserted and removed from the hole in the auto-tensioner.
- Remove the set wire attached to the auto-tensioner.
- Measure the auto-tensioner protrusion (the distance between the tensioner arm and auto-tensioner body) to ensure that it is within 0.150-0.196 in. (3.8-5.0mm). If out of specification, repeat adjustment procedure until the specified value is obtained.
- Check again that the timing marks on all sprockets are in proper alignment.
- Install the timing belt covers and all other applicable components.
- Disconnect the negative battery cable.
- Remove the engine undercover.
- Rotate the crankshaft clockwise and position the engine at TDC of the compression stroke.
- Raise and safely support the weight of the engine using the appropriate equipment. Remove the A/C clamp, front engine mount bracket and accessory drive belts.
- Remove the crankshaft pulley.
- Remove timing belt upper and lower covers.
- Make a mark on the back of the timing belt indicating the direction of rotation so it may be reassembled in the same direction if it is to be reused. Loosen the timing belt tensioner and move the tensioner to provide slack to the timing belt. Tighten the tensioner in this position.
- Remove the timing belt.
WARNINGCoolant and engine oil will damage the rubber in the timing belt, drastically reducing its life. Do not allow engine oil or coolant to contact the timing belt, the sprockets or tensioner assembly. - If defective, remove the tensioner spacer, tensioner spring and tensioner assembly.
To install:
- Position the tensioner, tensioner spring and tensioner spacer on engine block.
- Align the timing marks on the camshaft sprocket and crankshaft sprocket. This will position No. 1 piston on TDC on the compression stroke.
- Position the timing belt on the crankshaft sprocket and keeping the tension side of the belt tight, set it on the camshaft sprocket, then the tensioner.
- Apply slight counterclockwise force to the camshaft sprocket to give tension to the belt and be sure all timing marks are aligned.
- Loosen the pivot side tensioner bolt and the slot side bolt. Allow the spring to remove the slack.
- Tighten the slot side tensioner bolt, then the pivot side bolt. If the pivot side bolt is tightened first, the tensioner could turn with bolt, causing over tension.
- Turn the crankshaft clockwise. Loosen the pivot side tensioner bolt, then the slot side bolt to allow the spring to take up any remaining slack. Tighten the slot bolt, then the pivot side bolt to 17 ft. lbs. (24 Nm).
- Install the timing belt covers and tighten the cover bolts to 84-96 inch lbs. (10-11 Nm). Install all other applicable components.
- Start the engine and check for leaks.
- Disconnect the negative battery cable.
- Remove the engine undercover.
- Rotate the crankshaft clockwise and position the engine at TDC of the compression stroke.
- Raise and safely support the weight of the engine using the appropriate equipment. Remove the A/C clamp, front engine mount bracket and accessory drive belts.
- Remove the crankshaft pulley.
- Remove timing belt upper and lower covers.
- Make a mark on the back of the timing belt indicating the direction of rotation so it may be reassembled in the same direction if it is to be reused. Loosen the timing belt tensioner and move the tensioner to provide slack to the timing belt. Tighten the tensioner in this position.
- Remove the timing belt.
WARNING
Coolant and engine oil will damage the rubber in the timing belt, drastically reducing its life. Do not allow engine oil or coolant to contact the timing belt, the sprockets or tensioner assembly.
- If defective, remove the tensioner spacer, tensioner spring and tensioner assembly.
To install:
- Position the tensioner, tensioner spring and tensioner spacer on engine block.
- Align the timing marks on the camshaft sprocket and crankshaft sprocket. This will position No. 1 piston on TDC on the compression stroke.
- Position the timing belt on the crankshaft sprocket and keeping the tension side of the belt tight, set it on the camshaft sprocket, then the tensioner.
- Apply slight counterclockwise force to the camshaft sprocket to give tension to the belt and be sure all timing marks are aligned.
- Loosen the pivot side tensioner bolt and the slot side bolt. Allow the spring to remove the slack.
- Tighten the slot side tensioner bolt, then the pivot side bolt. If the pivot side bolt is tightened first, the tensioner could turn with bolt, causing over tension.
- Turn the crankshaft clockwise. Loosen the pivot side tensioner bolt, then the slot side bolt to allow the spring to take up any remaining slack. Tighten the slot bolt, then the pivot side bolt to 17 ft. lbs. (24 Nm).
- Install the timing belt covers and tighten the cover bolts to 84-96 inch lbs. (10-11 Nm). Install all other applicable components.
- Position the engine so the No. 1 piston is at TDC of the compression stroke.
- Disconnect the negative battery cable.
- Remove the engine undercover.
- Using the proper equipment, slightly raise the engine to take the weight off the side engine mount. Remove the engine mount bracket.
- Remove the drive belts, tension pulley brackets, water pump pulley and crankshaft pulley.
- Remove all attaching screws and remove the upper and lower timing belt covers.
- Remove the timing belt covers.
- Remove the outer crankshaft sprocket and flange.
- Remove the silent shaft (inner) belt tensioner and remove the belt.
To install:
- Align the timing marks of the silent shaft sprockets and the crankshaft sprocket with the timing marks on the front case.
- Wrap the timing belt around the sprockets so there is no slack in the upper span of the belt and the timing marks are still aligned.
- Install the tensioner pulley and move the pulley by hand so the long side of the belt deflects about 1 / 4 in. (6mm).
- Hold the pulley tightly so the pulley cannot rotate when the bolt is tightened. Tighten the bolt to 15 ft. lbs. (20 Nm) and recheck the deflection amount.
- Install the timing belt tensioner fully toward the water pump and tighten the bolts. Place the upper end of the spring against the water pump body.
- Align the timing marks of the camshaft, crankshaft and oil pump sprockets with their corresponding marks on the front case or rear cover.
NOTE
There is a possibility to align all timing marks and have the oil pump sprocket and silent shaft out of time, causing an engine vibration during operation. If the following step is not followed exactly, there is a 50 percent chance that the silent shaft alignment will be 180 degrees off.
- Before installing the timing belt, ensure that the left side (rear) silent shaft (oil pump sprocket) is in the correct position as follows:
- Remove the plug from the rear side of the block and insert a tool with shaft diameter of 0.31 in. (8mm) into the hole.
- With the timing marks still aligned, the shaft of the tool must be able to go in at least 21 / 3 in. (59mm). If the tool can only go in about 1 in. (25mm), the shaft is not in the correct orientation and will cause a vibration during engine operation. Remove the tool from the hole and turn the oil pump sprocket 1 complete revolution. Realign the timing marks and insert the tool. The shaft of the tool must go in at least 2 1 /3 in. (59mm).
- Recheck and realign the timing marks.
- Leave the tool in place to hold the silent shaft while continuing.
- Install the belt to the crankshaft sprocket, oil pump sprocket, then camshaft sprocket, in that order. While doing so, make sure there is no slack between the sprocket except where the tensioner is installed.
- Recheck the timing marks' alignment. If all are aligned, loosen the tensioner mounting bolt and allow the tensioner to apply tension to the belt.
- Remove the tool that is holding the silent shaft and rotate the crankshaft a distance equal to 2 teeth on the camshaft sprocket. This will allow the tensioner to automatically apply the proper tension on the belt. Do not manually overtighten the belt or it will howl.
- Tighten the lower mounting bolt first, then the upper spacer bolt.
- To verify correct belt tension, check that the deflection at the longest span of the belt is about 1 / 2 in. (13mm).
- The installation of the timing belt covers and all related items, is the reverse of the removal procedure. Make sure all pieces of packing are positioned in the inner grooves of the covers when installing.
- Connect the negative battery cable.
- Position the engine so the No. 1 piston is at TDC of the compression stroke.
- Disconnect the negative battery cable.
- Remove the engine undercover.
- Using the proper equipment, slightly raise the engine to take the weight off the side engine mount. Remove the engine mount bracket.
- Remove the drive belts, tension pulley brackets, water pump pulley and crankshaft pulley.
- Remove all attaching screws and remove the upper and lower timing belt covers.
- Remove the timing belt covers.
- Remove the outer crankshaft sprocket and flange.
- Remove the silent shaft (inner) belt tensioner and remove the belt.
To install:
- Align the timing marks of the silent shaft sprockets and the crankshaft sprocket with the timing marks on the front case.
- Wrap the timing belt around the sprockets so there is no slack in the upper span of the belt and the timing marks are still aligned.
- Install the tensioner pulley and move the pulley by hand so the long side of the belt deflects about 1 / 4 in. (6mm).
- Hold the pulley tightly so the pulley cannot rotate when the bolt is tightened. Tighten the bolt to 15 ft. lbs. (20 Nm) and recheck the deflection amount.
- Install the timing belt tensioner fully toward the water pump and tighten the bolts. Place the upper end of the spring against the water pump body.
- Align the timing marks of the camshaft, crankshaft and oil pump sprockets with their corresponding marks on the front case or rear cover.
NOTEThere is a possibility to align all timing marks and have the oil pump sprocket and silent shaft out of time, causing an engine vibration during operation. If the following step is not followed exactly, there is a 50 percent chance that the silent shaft alignment will be 180 degrees off. - Before installing the timing belt, ensure that the left side (rear) silent shaft (oil pump sprocket) is in the correct position as follows:
- Remove the plug from the rear side of the block and insert a tool with shaft diameter of 0.31 in. (8mm) into the hole.
- With the timing marks still aligned, the shaft of the tool must be able to go in at least 2 1 / 3 in. (59mm). If the tool can only go in about 1 in. (25mm), the shaft is not in the correct orientation and will cause a vibration during engine operation. Remove the tool from the hole and turn the oil pump sprocket 1 complete revolution. Realign the timing marks and insert the tool. The shaft of the tool must go in at least 2 1 / 3 in. (59mm).
- Recheck and realign the timing marks.
- Leave the tool in place to hold the silent shaft while continuing.
- Install the belt to the crankshaft sprocket, oil pump sprocket, then camshaft sprocket, in that order. While doing so, make sure there is no slack between the sprockets except where the tensioner is installed.
- Recheck the timing marks' alignment. If all are aligned, loosen the tensioner mounting bolt and allow the tensioner to apply tension to the belt.
- Remove the tool that is holding the silent shaft and rotate the crankshaft a distance equal to 2 teeth on the camshaft sprocket. This will allow the tensioner to automatically apply the proper tension on the belt. Do not manually overtighten the belt or it will howl.
- Tighten the lower mounting bolt first, then the upper spacer bolt.
- To verify correct belt tension, check that the deflection at the longest span of the belt is about 1 / 2 in. (13mm).
- The installation of the timing belt covers and all related items, is the reverse of the removal procedure. Make sure all pieces of packing are positioned in the inner grooves of the covers when installing.
- Connect the negative battery cable.
- Remove the left side engine under cover. Disconnect the negative battery cable. Remove the engine mounting insulator.
- Remove the crankshaft pulley.
- Disconnect the crankshaft position sensor connection. Remove the timing belt front upper cover.
- Disconnect the pressure hose clamp. Remove the power steering oil line bracket.
- Remove the alternator adjusting brace. Remove the timing belt lower cover.
- Remove the power steering pump bracket stay.
- Remove the flange. Remove the engine support bracket.
- Turn the crankshaft clockwise to align each timing mark and set the number one cylinder to TDC on the compression stroke. If the belt is going to be reused, mark the direction of rotation.
- Loosen the tension pulley retaining bolt. Position a suitable tool against the tensioner pulley and pry it fully back in the direction of the arrow in the illustration. Temporarily tighten the tensioner pulley bolt.
- Remove the timing belt. Remove the auto tensioner, tensioner pulley and tensioner arm
To install:
- With the timing belt tensioner pulley bolt loosened, use a suitable tool and pry the tensioner pulley as close to the engine mount as possible. Temporarily tighten the tensioner bolt.
- Align each of the crankshaft and camshaft sprocket timing marks.
- Install the timing belt in the following order. Crankshaft sprocket, then water pump sprocket, then camshaft sprocket and finally tensioner pulley.
NOTEAfter installing the belt, try to rotate the camshaft sprocket in the reverse direction. Recheck to be sure that the belt is fully tensioned and that each timing mark is in the proper direction.
- Initially loosen the fixing bolt of the tensioner pulley fixed to the engine mount side by ¼ to ½ turn. Use the force of the tensioner spring to apply tension to the belt.
NOTEAs the purpose of this procedure is to apply the proper amount of tension to the tension side of the timing belt by using the cam driving torque, turn the crankshaft only by the amount given below. Do not turn the crankshaft in the opposite direction (counterclockwise). - Turn the crankshaft in the clockwise direction for two rotations, and recheck to be sure that the timing marks on each sprocket are aligned.
- After checking to be sure that no belt teeth in the section marked -A- in the illustration are lifted up and that the teeth in each sprocket are engaged, secure the tensioner pulley.
- Install the flange.
- Continue the installation in the reverse order of the removal procedure.
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