Timing Belt
Removal & Installation
2.2L And 2.5L Engines
- Before servicing the vehicle, refer to the Precautions section.
When servicing the timing belt, note the following:
- The intake and exhaust camshafts can be rotated independently when the timing belt is removed. If the intake and exhaust valves are lifted off of their seats simultaneously, their heads will contact each other, possibly causing damage.
- When the timing belt is removed, the camshafts are positioned so that none of the valves are lifted off of their seats, resulting in a -zero-lift- position.
- The left-hand cylinder head camshafts must be rotated from the -zero-lift- position as little as possible when orienting it for timing belt installation, otherwise possible valve head interference may occur.
- Never allow the camshafts to rotate in the direction shown in the accompanying illustration, which would cause both the intake and exhaust valves to lift simultaneously, causing interference.
- Remove all necessary components to gain access to the timing belt.
- If equipped with manual transmissions, loosen the 2 timing belt guide mounting bolts, then separate the guide from the engine block.
- If the directional arrow and alignment marks on the timing belt are faded, and the belt is to be reused, remark the belt with white paint or a grease pencil as follows:
- Using a Subaru tool No. ST-499987500 Crankshaft Socket, or equivalent, installed on the crankshaft sprocket, rotate the crankshaft until the crankshaft sprocket, left-hand exhaust camshaft sprocket, left-hand intake camshaft sprocket, right-hand intake camshaft sprocket and right-hand exhaust camshaft sprocket timing mark notches are aligned with the respective marks on the belt cover and engine block.
- Make alignment and/or arrow marks on the timing belt in relation to the sprockets as indicated in the accompanying illustration.
Z1: 44 tooth length on all 2.2L engines and 2000 2.5L engines and 46.8 tooth length on 2001-04 2.5L enginesZ2: 40.5 tooth length on all 2.2L engines and 2000 2.5L engines or 43.7 tooth length on 2001-04 2.5L engines - Loosen the center bolt from the timing belt idler pulley, then remove the idler pulley from the engine block.
WARNING
After removing the timing belt, DO NOT rotate the camshafts. Damage to the valves may occur.
- Carefully remove the timing belt from all of the sprockets.
- Remove the automatic belt tension adjuster assembly as follows:
- Remove the 2 timing belt idler pulleys, as indicated in the accompanying illustration.
- Loosen the automatic tension adjuster assembly mounting bolts, then separate the adjuster assembly from the engine block.
To install:
WARNING
Do not allow oil, grease, or coolant to come in contact with the timing belt. If this occurs, quickly and thoroughly remove all traces of the compound. Also, never bend the timing belt sharply; the minimum bending radius is 2.36 in. (60mm).
- Inspect the camshaft and crankshaft sprocket teeth for abnormal or excessive wear or scratches. Ensure there is no free-play between the sprocket and the key. Inspect the crankshaft sprocket sensor notch for damage or contamination with debris or dirt.
NOTE
When preparing the automatic tension adjuster assembly for installation, adhere to the following points:
Always use a vertical press, rather than a horizontal press or vise, to depress the adjuster assembly rodDepress the adjuster rod in a vertical position ONLYDepress the adjuster rod slowly (taking more than 3 minutes) with a force of 66 lbs. (30 kg)Do not allow the press force to exceed 2205 lbs. (1000 kg)Press the adjuster rod in as far as the end surface of the cylinder - do not press the rod into the cylinder, which may cause damage to the assemblyDo not release the press force from the rod until the stopper pin is completely inserted in the cylinder
- Prepare the automatic timing belt tension adjuster assembly for installation as follows:
- Position the adjuster assembly in a vertical press.
- Slowly depress the adjuster rod with a force of 66 lbs. (30 kg) until the hole in the rod is aligned with the hole in the adjuster cylinder housing.
- Insert a 0.08 in. (2mm) diameter stopper pin or Allen wrench through the hole in the cylinder housing and rod, then slowly release the press force from the adjuster rod.
- Install the adjuster assembly onto the engine block.
- Install timing belt idler pulley No. 2 on the engine block. Tighten the bolts to 28 ft. lbs. (39 Nm).
- Install the timing belt idler pulley No. 1 on the engine block. Tighten the bolts to 28 ft. lbs. (39 Nm).
- If the camshaft and crankshaft timing marks are no longer aligned, perform the following:
- Position the crankshaft sprocket so that its mark is aligned with the mark on the oil pump cover on the engine block.
- Align the single line mark on the right-hand exhaust camshaft sprocket with the notch on the belt cover.
- Rotate the right-hand intake camshaft so that the single line mark is aligned with the notch on the belt cover.
NOTE
At this point, the double line marks on both right-hand camshaft sprockets should be aligned.
- Turn the left-hand exhaust (lower) camshaft counterclockwise (as viewed from the front of the engine) until the single line mark is aligned with the notch on the belt cover.
- Position the single line mark on the left-hand intake camshaft sprocket so that it is aligned with the notch on the belt cover. When rotating the camshaft, do so only in a clockwise direction (as viewed from the front of the engine).
NOTE
At this point, the double line marks on both left-hand camshaft sprockets should be aligned.
- Ensure the timing marks are aligned as shown in the accompanying illustration. If they are not, repeat Sub steps 12a through 12e until they are properly aligned.
- Install the timing belt around the camshaft, crankshaft and idler pulleys so that the positioning marks on the timing belt are aligned with the marks on the sprockets as follows:
- Position the timing belt on the crankshaft sprocket so that the marks are aligned.
- Route the belt down and under the left-hand, upper idler pulley, then up and around the left-hand intake camshaft sprocket, ensuring the camshaft sprocket mark is aligned with the mark on the belt.
- Route the belt down and around the left-hand exhaust camshaft sprocket, making sure the marks are properly aligned, then up and over the first lower idler pulley and down and around the second lower idler pulley.
- While holding the timing belt on the inner, left-hand, lower idler pulley, route the other side of the timing belt (from the crankshaft sprocket) down and under the right-hand upper idler pulley.
- Route the timing belt up and around the right-hand intake camshaft sprocket so that the belt and sprocket marks are aligned.
- Position the belt down and around the right-hand exhaust camshaft sprocket, ensuring the positioning marks are aligned.
- Install the right-hand lower idler pulley so that the timing belt is routed over the top side of it.
NOTE
Once the belt is completely installed on all of the pulleys and sprockets, ensure that the positioning marks are still all aligned.
- After ensuring all of the marks are still aligned, use a pair of pliers to withdraw the stopper pin or Allen wrench from the adjuster assembly housing.
- On models with manual transmissions, perform the following:
- Install the timing belt covers and all remaining engine components.
The engine uses a single cam belt drive system with a serpentine type belt. The left side of the engine uses a hydraulic cam belt tensioner, which is self-adjusting.
NOTE
It is recommended that the timing belt be replaced at least every 60,000 miles (96,618 km).
- Disconnect the negative battery cable.
- Position the No. 1 piston to Top Dead Center (TDC) of its compression stroke.
- Remove the engine drive belts.
- Remove the timing belt covers.
- Align the camshaft sprockets so each sprocket notch aligns with the cam cover notches. Align the crankshaft sprocket top tooth notch, located at the rear of the tooth, with the notch on the crank angle sensor boss. Mark the three alignment points as well as the direction of cam belt rotation.
- Loosen the tensioner adjusting bolts. Remove the bottom three idlers, the cam belt and the cam belt tensioner. The cam sprockets can, then be removed with a modified camshaft sprocket wrench tool.
- Remove the sprockets, if necessary. Note the reference sensor at the rear of the left cam sprocket.
To install:
- Install the sprockets, if removed and tighten the retaining bolts to 47-54 ft. lbs. (64-74 Nm).
- Install the crankshaft sprocket and the non-adjustable right side idler. Do not install the tensioner idler at this time.
- Compress the hydraulic tensioner in a vise slowly and temporarily secure the plunger with a pin or suitable Allen wrench. Install the tensioner and the pulley with the adjustable idler pulley. Temporarily tighten the tensioner while the tensioner is pushed to the right.
- Align the crankshaft sprocket notch on the rear sprocket tooth with the crank angle sensor boss. This places the sprocket notch in the 12 o'clock position.
- Align the camshaft sprockets with the notches in the cam rear belt cover. This places the sprocket notch in the 12 o'clock position for each camshaft.
- Install the timing belt with the directional mark and alignment marks properly positioned (if the belt is reused).
- Loosen the tensioner retaining bolts and slide the tensioner to the left. Tighten the mounting bolts.
- After verifying the timing marks are correct, remove the stopper pin from the tensioner.
- Verify the correctness of the timing by noting that the notches on the 2 cam pulleys and the notch on the crankshaft pulley all point to the 12 o'clock position when the belt is properly installed.
- Complete the engine component assembly by installing the cam belt covers, the crankshaft pulley bolt and pulley and the remaining components.
- Connect the negative battery cable.
The engine uses a single cam belt drive system with a serpentine type belt. The left side of the engine uses a hydraulic cam belt tensioner, which is self-adjusting.
NOTE
It is recommended that the timing belt be replaced at least every 60,000 miles (96,618 km).
- Remove all necessary components for access to the left, right and center timing belt covers, then remove the covers.
- Align the camshaft sprockets so each sprocket notch aligns with the rear cover notches. Align the crankshaft sprocket top tooth notch, located at the rear of the tooth with the notch. The crankshaft notch will be at 12 o'clock and the keyway will be at 6 o'clock.NOTEMark the sprocket alignment points as well as the direction of cam belt rotation for reinstallation purposes if the belt is to be reused.
- Loosen the tensioner adjusting bolts.
- Remove the lower timing belt idler.
- Remove the timing belt from the pulleys.WARNINGAfter the timing belt is removed, DO NOT rotate the camshaft sprockets or the crankshaft. Severe internal damage will result from the valve and/or piston contact.
- Remove the timing belt tensioner and the timing belt tension adjuster.
To install:
NOTE
Inspect the timing belt and tensioner for wear or damage and replace as necessary.
- Inspect the timing belt tensioner as follows:
- When compressing the pushrod of the tensioner with a force of 33 lbs. (147 N), the tensioner should not sink.
- When compressing the pushrod of the tensioner with a force of 33-110 lbs. (147-490 N), the tensioner should not sink within 8.5 seconds.
- Measure the extension of the rod beyond the body of the tensioner for a length of 0.606-0.646 in. (15.4-16.4mm). If not within specifications, replace the tensioner.NOTECheck the idler sprockets for smooth operation. Replace as necessary.
- Using a press, compress the tensioner gradually, taking three minutes or more, and insert a 0.059 in. (1.5mm) pin to secure the rod.
- Install the tensioner and the pulley with the adjustable idler pulley. Temporarily tighten the tensioner while the tensioner is pushed to the right.
- Align the crankshaft sprocket notch on the rear sprocket tooth with the crank angle sensor boss. This places the sprocket notch in the 12 o'clock position and the key way at the 6 o'clock position.
- Align the camshaft sprockets with the notches in the cam rear belt cover. This places the sprocket notch in the 12 o'clock position for each camshaft.
- Install the timing belt in a clockwise direction starting at the crankshaft with the directional mark and alignment marks properly positioned (if the belt was reused).
- Install the lower timing belt idler and tighten the mounting bolt to 29 ft. lbs. (39 Nm).WARNINGBe sure all the timing marks are properly aligned.
- Loosen the tensioner retaining bolts and slide the tensioner to the left. Tighten the mounting bolts to 18 ft. lbs. (25 Nm).
- After verifying the timing marks are correct, remove the stopper pin from the tensioner and recheck the timing marks.
- Install the center, right, then the center timing belt covers. Tighten the bolts to 44 inch lbs. (5 Nm).
- Install the remaining components in the reverse order of the removal procedure. When installing the crankshaft sprocket, be sure to tighten the mounting bolt to 94 ft. lbs. (127 Nm).
The engine uses a single cam belt drive system with a serpentine type belt. The left side of the engine uses a hydraulic cam belt tensioner which is self-adjusting.
NOTE
It is recommended that the timing belt be replaced every 60,000 miles (96,618 km).
- Before servicing the vehicle, refer to the Precautions section.
- Disconnect the negative battery cable.
- Disconnect the radiator electric fan motor wiring connectors.
- Remove the coolant reservoir tank.
- Remove the four bolts that secure the radiator shroud and remove the fan assembly.
- Position the No. 1 piston to TDC of its compression stroke.
- Remove the engine drive belts.
- Remove the A/C compressor drive belt tensioner.
- Using holding tool ST499977000 or equivalent, remove the bolt that secures the crankshaft sprocket and remove the sprocket.
- Remove the left, right then the center timing belt covers.
- Align the camshaft sprockets so each sprocket notch aligns with the rear cover notches. Align the crankshaft sprocket top tooth notch, located at the rear of the tooth with the notch. The crankshaft notch will be at 12 o'clock and the keyway will be at 6 o'clock.NOTEMark the sprocket alignment points as well as the direction of cam belt rotation for reinstallation purposes if the belt is to be reused.
- Loosen the tensioner adjusting bolts.
- Remove the lower timing belt idler.
- Remove the timing belt from the pulleys.WARNINGAfter the timing belt is removed, DO NOT rotate the camshaft sprockets or the crankshaft. Severe internal damage will result from the valve and/or piston contact.
- Remove the timing belt tensioner and the timing belt tension adjuster.
To install:
NOTE
Inspect the timing belt and tensioner for wear or damage and replace as necessary.
- Inspect the timing belt tensioner as follows:
- When compressing the pushrod of the tensioner with a force of 33 lbs. (147 N), the tensioner should not sink.
- When compressing the pushrod of the tensioner with a force of 33-110 lbs. (147-490 N), the tensioner should not sink within 8.5 seconds.
- Measure the extension of the rod beyond the body of the tensioner for a length of 0.606-0.646 inch (15.4-16.4mm). If not within specifications, replace the tensioner.NOTECheck the idler sprockets for smooth operation. Replace as necessary.
- Using a press, compress the tensioner gradually, taking three minutes or more, and insert a 0.059 inch (1.5mm) pin to secure the rod.
- Install the tensioner and the pulley with the adjustable idler pulley. Temporarily tighten the tensioner while the tensioner is pushed to the right.
- Align the crankshaft sprocket notch on the rear sprocket tooth with the crank angle sensor boss. This places the sprocket notch in the 12 o'clock position and the and the key way at the 6 o'clock position.
- Align the camshaft sprockets with the notches in the cam rear belt cover. This places the sprocket notch in the 12 o'clock position for each camshaft.
- Install the timing belt in a clockwise direction starting at the crankshaft with the directional mark and alignment marks properly positioned (if belt was reused).
- Install the lower timing belt idler and tighten the mounting bolt to 29 ft. lbs. (39 Nm).WARNINGMake sure all the timing marks are properly aligned.
- Loosen the tensioner retaining bolts and slide the tensioner to the left. Tighten the mounting bolts to 18 ft. lbs. (25 Nm).
- After verifying the timing marks are correct, remove the stopper pin from the tensioner and recheck the timing marks.
- Install the center, right and then the center timing belt covers. Torque the bolts to 44 inch lbs. (5 Nm).
- Install the crankshaft sprocket and tighten the mounting bolt to 94 ft. lbs. (127 Nm) while securing the crankshaft pulley.
- Install the A/C drive belt tensioner.
- Install the engine drive belts.
- Install the fan shroud and motor assembly.
- Connect the negative battery cable.
When servicing the timing belt, note the following:
- The intake and exhaust camshafts can be rotated independently when the timing belt is removed. If the intake and exhaust valves are lifted off of their seats simultaneously, their heads will contact each other, possibly causing damage.
- When the timing belt is removed, the camshafts are positioned so that none of the valves are lifted off of their seats, resulting in a -zero-lift- position.
- The left-hand cylinder head camshafts must be rotated from the -zero-lift- position as little as possible when orienting it for timing belt installation, otherwise possible valve head interference may occur.
- Never allow the camshafts to rotate in the direction shown in the accompanying illustration, which would cause both the intake and exhaust valves to lift simultaneously, causing interference.
- Remove all necessary components to gain access to the timing belt.
- If equipped with manual transmissions, loosen the 2 timing belt guide mounting bolts, then separate the guide from the engine block.
- If the directional arrow and alignment marks on the timing belt are faded, and the belt is to be reused, remark the belt with white paint or a grease pencil as follows:
- Using a Subaru tool No. ST-499987500 Crankshaft Socket, or equivalent, installed on the crankshaft sprocket, rotate the crankshaft until the crankshaft sprocket, left-hand exhaust camshaft sprocket, left-hand intake camshaft sprocket, right-hand intake camshaft sprocket and right-hand exhaust camshaft sprocket timing mark notches are aligned with the respective marks on the belt cover and engine block.
- Make alignment and/or arrow marks on the timing belt in relation to the sprockets as indicated in the accompanying illustration.Z1: 46.8 tooth lengthZ2: 43.7 tooth length
- Using a Subaru tool No. ST-499987500 Crankshaft Socket, or equivalent, installed on the crankshaft sprocket, rotate the crankshaft until the crankshaft sprocket, left-hand exhaust camshaft sprocket, left-hand intake camshaft sprocket, right-hand intake camshaft sprocket and right-hand exhaust camshaft sprocket timing mark notches are aligned with the respective marks on the belt cover and engine block.
- Loosen the center bolt from the timing belt idler pulley, then remove the idler pulley from the engine block.WARNINGAfter removing the timing belt, DO NOT rotate the camshafts. Damage to the valves may occur.
- Carefully remove the timing belt from all of the sprockets.
- Remove the automatic belt tension adjuster assembly as follows:
- Remove the 2 timing belt idler pulleys, as indicated in the accompanying illustration.
- Loosen the automatic tension adjuster assembly mounting bolts, then separate the adjuster assembly from the engine block.
To install:
WARNING
Do not allow oil, grease, or coolant to come in contact with the timing belt. If this occurs, quickly and thoroughly remove all traces of the compound. Also, never bend the timing belt sharply; the minimum bending radius is 2.36 in. (60mm).
- Inspect the camshaft and crankshaft sprocket teeth for abnormal or excessive wear or scratches. Ensure there is no free-play between the sprocket and the key. Inspect the crankshaft sprocket sensor notch for damage or contamination with debris or dirt.NOTEWhen preparing the automatic tension adjuster assembly for installation, adhere to the following points:Always use a vertical press, rather than a horizontal press or vise, to depress the adjuster assembly rodDepress the adjuster rod in a vertical position ONLYDepress the adjuster rod slowly (taking more than 3 minutes) with a force of 66 lbs. (30 kg)Do not allow the press force to exceed 2205 lbs. (1000 kg)Press the adjuster rod in as far as the end surface of the cylinder - do not press the rod into the cylinder, which may cause damage to the assemblyDo not release the press force from the rod until the stopper pin is completely inserted in the cylinder
- Prepare the automatic timing belt tension adjuster assembly for installation as follows:
- Position the adjuster assembly in a vertical press.
- Slowly depress the adjuster rod with a force of 66 lbs. (30 kg) until the hole in the rod is aligned with the hole in the adjuster cylinder housing.
- Insert a 0.08 in. (2mm) diameter stopper pin or Allen wrench through the hole in the cylinder housing and rod, then slowly release the press force from the adjuster rod.
- Install the adjuster assembly onto the engine block.
- Install timing belt idler pulley No. 2 on the engine block. Tighten the bolts to 28 ft. lbs. (39 Nm).
- Install the timing belt idler pulley No. 1 on the engine block. Tighten the bolts to 28 ft. lbs. (39 Nm).
- If the camshaft and crankshaft timing marks are no longer aligned, perform the following:
- Position the crankshaft sprocket so that its mark is aligned with the mark on the oil pump cover on the engine block.
- Align the single line mark on the right-hand exhaust camshaft sprocket with the notch on the belt cover.
- Rotate the right-hand intake camshaft so that the single line mark is aligned with the notch on the belt cover.NOTEAt this point, the double line marks on both right-hand camshaft sprockets should be aligned.
- Turn the left-hand exhaust (lower) camshaft counterclockwise (as viewed from the front of the engine) until the single line mark is aligned with the notch on the belt cover.
- Position the single line mark on the left-hand intake camshaft sprocket so that it is aligned with the notch on the belt cover. When rotating the camshaft, do so only in a clockwise direction (as viewed from the front of the engine).NOTEAt this point, the double line marks on both left-hand camshaft sprockets should be aligned.
- Ensure the timing marks are aligned as shown in the accompanying illustration. If they are not, repeat Sub steps 12a through 12e until they are properly aligned.
- Position the crankshaft sprocket so that its mark is aligned with the mark on the oil pump cover on the engine block.
- Install the timing belt around the camshaft, crankshaft and idler pulleys so that the positioning marks on the timing belt are aligned with the marks on the sprockets as follows:
- Position the timing belt on the crankshaft sprocket so that the marks are aligned.
- Route the belt down and under the left-hand, upper idler pulley, then up and around the left-hand intake camshaft sprocket, ensuring the camshaft sprocket mark is aligned with the mark on the belt.
- Route the belt down and around the left-hand exhaust camshaft sprocket, making sure the marks are properly aligned, then up and over the first lower idler pulley and down and around the second lower idler pulley.
- While holding the timing belt on the inner, left-hand, lower idler pulley, route the other side of the timing belt (from the crankshaft sprocket) down and under the right-hand upper idler pulley.
- Route the timing belt up and around the right-hand intake camshaft sprocket so that the belt and sprocket marks are aligned.
- Position the belt down and around the right-hand exhaust camshaft sprocket, ensuring the positioning marks are aligned.
- Install the right-hand lower idler pulley so that the timing belt is routed over the top side of it.NOTEOnce the belt is completely installed on all of the pulleys and sprockets, ensure that the positioning marks are still all aligned.
- After ensuring all of the marks are still aligned, use a pair of pliers to withdraw the stopper pin or Allen wrench from the adjuster assembly housing.
- On vehicles with manual transmissions, perform the following:
- Install the timing belt covers and all remaining engine components.
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