How to replace alternator belt for 1984 Mercedes 190E.

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The power steering pump has has mounting bolts that also serve to hold tension on the belt. Same for the alternator. Loosen the bolts but don't take completely out, push the pump or alternator towards the engine to release tension. Replace the belts. Use a long handled pry bar to push against the alternator or power steering pump to apply tension to the new belt while simultaneously tighten the bolts.

Check to see if there is a tensioner pully that adjust the belt tightness. The tension pulley a small pulley will have two bolts on it one of them loosens and tightens the belt around the alternator and compressor USUALLY.

ADJUSTMENT

Excessive belt tension will cause damage to the alternator and water pump pulley bearings, while, on the other hand, loose belt tension will produce slip and premature wear on the belt. Therefore, be sure to adjust the belt tension to the proper level.
To adjust the tension on a drive belt, loosen the adjusting bolt or fixing bolt locknut on the alternator, alternator bracket or tension pulley. Then move the alternator or turn the adjusting bolt to adjust belt tension. Once the desired value is reached, secure the bolt or locknut and recheck tension.

REMOVAL & INSTALLATION

1.5L, 1.6L, 1.8L, 2.0L and 2.4L Engines

Fig. Accessory V-belt routing-Mitsubishi 1.5L, 1.6L, 1.8L, 2.0L and 2.4L engines
Alternator Belt

Fig. Loosen the adjuster lock bolt . . .

Fig. . . . then remove the alternator belt from the engine

1. Loosen the alternator support nut.
2. Loosen the adjuster lock bolt.
3. Rotate the adjuster bolt counter clockwise to release the tension on the belt.
4. Remove the belt.

To install:

1. Install the belt on the pulleys.
2. Rotate the adjuster bolt clockwise until the proper tension is reached.
3. Tighten the adjuster lock bolt and the alternator support nut.

POWER STEERING BELT

Fig. After the adjusting and fixed bolts are loosened, rotate the pump . . .

Fig. . . . then remove the power steering belt from the engine

1. Remove the alternator belt as described above.
2. Loosen the power steering pump adjusting bolts.
3. Remove the power steering pump fixed bolt on the rear of the bracket.
4. Rotate the pump toward the engine and remove the belt.

To install:

1. Install the belt on the pulleys.
2. Rotate the pump until the proper tension is reached.
3. Tighten the adjusting bolts on the pump.
4. Tighten the fixed bolt on the rear of the bracket.
5. Install the alternator belt.

A/C COMPRESSOR BELT

1. Loosen the tension pulley and remove the belt.
2. The installation is the reverse of the removal.

3.0L DOHC, 3.0L SOHC Galant, and 3.5L Engines

Fig. Serpentine belt routing-Mitsubishi 3.0L engines (except 1998-00 Galant models)

Fig. Accessory V-belt routing-Mitsubishi 3.5L and 1998-00 3.0L SOHC Galant engines
ALTERNATOR AND A/C COMPRESSOR

1. Disconnect the negative battery cable.

CAUTION Wait at least 90 seconds after the negative battery cable is disconnected to prevent possible deployment of the air bag.

1. Raise and safely support the vehicle and remove the front undercover.
2. Loosen the tension pulley fixing nut and relieve the tension on the belt by turning the adjusting bolt.
3. Remove the belt.

To install:

1. Install the belt on the crankshaft and alternator pulleys.
2. Using the adjusting bolt on the tensioner, tighten the belt to the desired tension.
3. Tighten the fixing nut to hold the adjustment.
4. Install the undercover and lower the vehicle to the floor.
5. Connect the negative battery cable.

POWER STEERING BELT

1. Disconnect the negative battery cable.

CAUTION Wait at least 90 seconds after the negative battery cable is disconnected to prevent possible deployment of the air bag.

1. Raise and safely support the vehicle and remove the undercover.
2. Remove the alternator and A/C compressor belt.
3. Lower the vehicle and remove the cruise control pump link assembly.
4. Place the power steering hose under the oil reservoir.
5. Loosen the tension pulley fixing bolts and remove the power steering pump drive belt.

To install:

1. Install the power steering pump drive belt.
2. Insert an extension bar or equivalent into the opening at the end of the tension pulley bracket and pivot the pulley to apply tension to the belt.
3. Tighten the fixing bolts.
4. Raise the vehicle and install the alternator and A/C compressor belt.
5. Install the undercover and lower the vehicle.
6. Connect the negative battery cable.

3.0L SOHC Diamante

1. Disconnect the negative battery cable.
2. Loosen the lockbolt on the face of the A/C tensioner pulley.
3. Turn the adjusting bolt of the A/C tensioner pulley to loosen the tension of the A/C belt.
4. Remove the A/C compressor belt.
5. Loosen the locknut on the face of the power steering/alternator tensioner pulley.
6. Turn the adjusting bolt of the tensioner pulley to loosen the tension of the belt.
7. Remove the power steering/alternator belt.

To install:

1. Install the power steering/alternator belt first and then the A/C compressor drive belt.
2. Adjust the belts to the proper tension by turning the adjusting bolts and tighten pulley fixing nut/bolt.
3. Tighten the mounting nut of the power steering/alternator tensioner pulley to 36 ft. lbs. (50 Nm).

Drive Belts

• INSPECTION
• ADJUSTMENT
• REMOVAL & INSTALLATION

Print

INSPECTION

See Figures 1, 2, 3, 4 and 5
Check the condition and tension of all drive belts every 12,000 miles, or at least once a year. Loose drive belts can lead to poor engine cooling and diminished alternator, power steering pump, air conditioning compressor, or emission air pump output. A belt that is too tight places a strain on the bearings in the driven component.

Fig. Fig. 1: There are typically 3 types of accessory drive belts found on vehicles today

Fig. Fig. 2: An example of a healthy drive belt

Fig. Fig. 3: Deep cracks in this belt will cause flex, building up heat that will eventually lead to belt failure

Fig. Fig. 4: The cover of this belt is worn, exposing the critical reinforcing cords to excessive wear

Fig. Fig. 5: Installing too wide a belt can result in serious belt wear and/or breakage
Replace any drive belt that is glazed, worn, cracked, or stretched to the point where correct adjustment tension is impossible. If two belts are used to drive a component, always replace both belts when replacement is necessary. After installing a new belt, run the engine for ten minutes, shut OFF the engine and recheck the belt tension. Readjust if necessary.

ADJUSTMENT

See Figures 6, 7, 8, 9 and 10

Fig. Fig. 6: Engine belt tension chart-2.2L engines

Fig. Fig. 7: Engine belt tension chart-1987-89 2.5L engines

Fig. Fig. 8: Engine belt tension chart-2.6L engines

Fig. Fig. 9: Engine belt tension chart-1990-93 models

Fig. Fig. 10: Engine belt tension chart-1994-95 models
Two popular methods of checking drive belt adjustment are; the Belt Tension Gauge Method and the Belt Deflection Method. The former requires a special gauge and the latter requires a straight edge and scale or just a good eye for measurement. The deflection method will be used in the following belt replacement instructions. A rule of thumb for checking belt tension by the deflection method is to determine the midpoint between two pulleys of the drive belt and press down at that point with moderate thumb pressure. The belt should deflect to the measurement indicated in the following installation procedures. Adjustment is necessary if the belt is either too loose or too tight.

WARNING A belt adjustment which is either too loose or too tight will eventually damage the accessory that belt is driving. A too loose adjustment allows free-play in the belt which could transfer a whipping motion or shock to the accessory drive pulley. Similarly, a belt which is too tight will preload the accessory bearings, leading to early failure.

REMOVAL & INSTALLATION

See Figure 11
Raise the front of the vehicle, support on jackstands and remove the lower splash shield if access is hampered due to space limitations when changing drive belts.

Fig. Fig. 11: Support the vehicle, then remove the lower right side splash shield for access to the drive belts
2.2L Engines
A/C COMPRESSOR DRIVE BELT
See Figures 12, 13 and 14

Fig. Fig. 12: A/C compressor drive belt adjusting points-2.2L engines

Fig. Fig. 13: Loosening the locking screws for A/C compressor drive belt removal

Fig. Fig. 14: Removing the A/C compressor drive belt from under the vehicle

1. Loosen the idler pulley bracket pivot screw and the locking screw.
2. Remove the belt and install a replacement.
3. Using a breaker bar and socket apply torque to the welded nut provided on the mounted bracket to obtain proper tension.
4. Tighten the locking screw first, followed by pivot screw. Tighten to 40 ft. lbs. (55 Nm).

ALTERNATOR DRIVE BELT (CHRYSLER TYPE)
See Figures 15 and 16

Fig. Fig. 15: Alternator belt adjustment-2.2L engine

Fig. Fig. 16: Loosening the locking screw for alternator drive belt removal
If removal of the alternator belt is required, the A/C belt must first be removed.

1. Loosen the pivot nut, locking screw, and the adjusting screw.
2. Remove the belt and install a replacement.
3. Adjust to specification by tightening the adjusting screw.
4. Tighten the locking screw to 25 ft. lbs. (34 Nm).
5. Tighten the pivot nut to 30 ft. lbs. (41 Nm).

ALTERNATOR DRIVE BELT (BOSCH TYPE)
If removal of the alternator belt is required, the A/C belt must first be removed.

1. Loosen the pivot nut, locking nut, and adjusting screw.
2. Remove the belt and install a replacement.
3. Adjust to specification by tightening the adjusting screw.
4. Tighten the locking nut to 25 ft. lbs. (34 Nm).
5. Tighten the pivot nut to 30 ft. lbs. (41 Nm).

POWER STEERING BELT
If removal of the power steering belt is required, the A/C and alternator belts must first be removed.

1. Loosen the locking screw, and pivot screw.
2. Remove the belt and install a replacement.
3. Install a 1 / 2 in. breaker bar into the pump bracket slot, apply pressure with the breaker bar and adjust the belt to specification.
4. Tighten the locking screw first, then the pivot screw. Tighten to 40 ft. lbs. (55 Nm).

AIR PUMP DRIVE BELT
See Figure 17

Fig. Fig. 17: Air pump belt adjustment-2.2L engines
When servicing the air pump, use the square holes provided in the pulley to prevent camshaft rotation.

1. Remove the nuts and bolts retaining the drive pulley cover.
2. Remove the locking bolt and pivot bolt from the pump bracket, then remove the pump.
3. Remove the belt and install a replacement.
4. Position the pump, then install the locking bolt and pivot bolt finger-tight.
5. Install a 1 / 2 in. breaker bar into the bracket assembly (block the drive pulley to prevent camshaft rotation), and adjust the belt to specification.
6. Tighten locking bolt and pivot bolt to 25 ft. lbs. (35 Nm).

2.5L Engines
AIR CONDITIONING COMPRESSOR
See Figure 18

Fig. Fig. 18: Drive belt adjustment points-2.5L engines

1. Loosen the idler bracket pivot screw and the locking screws to replace, or adjust belt.
2. Remove the belt and install a replacement.
3. Adjust the belt to specification by applying torque to weld nut on the idler bracket.
4. Tighten locking screw first, followed by the pivot screw. Tighten to 40 ft. lbs. (55 Nm).

ALTERNATOR BELT
See Figure 18
If replacement of the alternator belt is required, the A/C drive belt must first be removed.

1. Loosen the pivot nut, locking nut, and adjusting screw.
2. Remove the belt and install a replacement.
3. Adjust the belt to specification by tightening the adjusting screw.
4. Tighten the locking nut to 25 ft. lbs. (35 Nm).
5. Tighten the pivot nut to 30 ft. lbs. (40 Nm).

POWER STEERING PUMP
See Figure 18
If replacement of the power steering belt is required, the A/C and alternator belts must first be remove.

1. Loosen the locking screw and pivot screw to replace, or adjust the belt.
2. Remove the belt and install a replacement.
3. Using a 1 / 2 in. breaker bar positioned in adjusting bracket slot, adjust the belt to specification.
4. Tighten the locking screw followed by the pivot screw. Tighten to 40 ft. lbs. (55 Nm).

2.6L Engines
ALTERNATOR/AIR CONDITIONING COMPRESSOR BELT
See Figure 19

Fig. Fig. 19: Drive belt adjustment points-2.6L engines

1. Loosen the locking screw, jam nut, and pivot nut.
2. Loosen the adjusting screw.
3. Remove the belt and install a replacement.
4. Adjust the belt to specification by tightening the adjusting screw.
5. Tighten the locking screw followed by the pivot nut. Tighten to 16 ft. lbs. (22 Nm).
6. Tighten the jam nut to 21 ft. lbs. (28 Nm).

POWER STEERING PUMP BELT
See Figure 19
If replacement of the power steering belt is required, the alternator and A/C belt must first be remove.

1. Loosen the pivot screw, and the locking screw.
2. Remove the timing pickup.
3. Remove the belt and install a replacement.
4. Install a 1 / 2 in. breaker bar in the adjusting bracket slot, torque to specification.
5. Tighten the locking screw, followed by the pivot screw. Tighten to 40 ft. lbs. (55 Nm).
6. Install the timing pick-up, and tighten to 160 inch lbs. (18 Nm).

The only way to replace an alternator drive belt that is on an inside pulley is to remove the outer belts before the inner one can be fitted.
To fit inner belt, loosen the adjusting clamp and mounting bolts on the units that tension the outer belts such as the aircon compressor and power steering units and moove them to loosen the belts and then remove these belts. Once these belts are off, check them for wear and cracking of the rubber on the inside surface and if suspect it would pay to replace them as well. Loosen clamp and mounting bolts on the alternator, if not already done so, and moove alternator so that alternator belt can be fitted.
Retension alternator belt and tighten clsmping and mounting bolts Refit other belts in turn and tension and tighten clamping and mounting bolts.
Correct tension is when belt is pushed on the longest run between pulleys with a 10 Kg force. Belt should deflect a maximum of 8 mm.

Timing Belt Removal & Installation SOHC To Remove:

1. Disconnect battery negative cable.
2. Remove fresh air duct.
3. Drain engine coolant into an appropriate container and retighten radiator drain plug.
4. Remove upper radiator hose.
5. Remove fan clutch assembly bolts.
6. Remove 5 cooling fan shroud bolts.
7. Remove fan shroud and fan as an assembly.
8. Loosen alternator mounting bolts and remove drive belt from pulley.
9. Remove fan pulley.
10. Remove 4 cooling fan assembly bolts.
11. Remove cooling fan assembly.
12. Remove 4 bolts and upper timing belt cover.
13. Remove 2 lower bolts and lower timing belt cover.
14. Loosen adjusting bolt and remove A/C belt.
15. Remove alternator belt.
16. Loosen power steering pump lock bolt and mounting bolt.
17. Remove drive belt from crankshaft damper. Camshaft timing marks
    
    
18. Turn crankshaft until timing mark on front housing and the arrow "2" on the camshaft pulley align.
19. Remove 5 bolts and remove damper.
20. Remove timing belt guide from timing belt pulley.
21. Loosen tensioner lock bolt.
22. Pry tensioner away from timing belt and tighten lock bolt to relieve tension on the timing belt. NOTE: Mark the direction of timing belt rotation on the belt if it is being reused.
    
23. Remove timing belt.

To Install:
Timing belt pulley timing marks

NOTE: Timing belt pulley timing mark and timing mark must be aligned.
Camshaft timing marks

NOTE: The arrow at "2" on camshaft pulley must be aligned with timing mark on front housing.
Timing belt installation

1. Install timing belt with minimal slack from timing belt pulley to water pump and from water pump to camshaft pulley.
2. Loosen tensioner lock bolt until tension is applied to timing belt. CAUTION
   Do not turn crankshaft counterclockwise.
   
3. Turn crankshaft pulley 2 full turns clockwise and ensure timing marks are properly aligned.
4. Tighten tensioner lock bolt to 33 ft lb (45 Nm).
5. Apply a force of 21 lb to timing belt midway between idler pulley and camshaft pulley.
   • Deflection should measure 0.43-0.51 inch (11-13 mm)
   NOTE: if timing belt deflection is incorrect remove timing belt and install NEW tensioner spring.
   
6. Install timing belt guide.
7. Install crankshaft damper pulley.
8. Install 5 crankshaft damper pulley bolts. Tighten bolts to 132 in lb (15 Nm).
9. Install power steering pump drive belt.
10. Adjust power steering pump drive belt tension and tighten lock bolt and mounting bolt.
11. Install alternator drive belt.
12. Install A/C drive belt.
13. Install lower timing belt cover and bolts. Tighten bolts to 84 in lb (10 Nm).
14. Install upper timing belt cover and bolts. Tighten bolts to 84 in lb (10 Nm).
15. Install cooling fan assembly and 4 bolts. Tighten bolts to 27 ft lb (37 Nm).
16. Install fan pulley.
17. Install fan clutch and shroud as an assembly. Tighten bolts to 74 in lb (8 Nm).
18. Tighten 4 cooling fan nuts to 16 ft lb (22 Nm).
19. Adjust alternator belt tension and tighten alternator mounting bolts.
20. Install upper radiator hose.
21. Install fresh air duct.
22. Connect battery negative cable.
23. Refill/bleed cooling system.

DOHC To Remove:

1. Disconnect battery negative cable.
2. Remove fresh air duct.
3. Remove 5 cooling fan shroud bolts and 4 thermo-modulated fan nuts.
4. Remove 4 thermo-modulated fan shroud fasteners.
5. Remove generator drive belt.
6. Remove fan pulley (located above crankshaft pulley).
7. Remove 4 bolts and splash shield (located under front of vehicle).
8. Remove A/C drive belt and power steering drive belt. Timing Belt Removal
   
   
9. Remove 5 bolts and upper timing belt cover.
10. Remove 2 bolts and lower timing belt cover.
11. Loosen tensioner lock bolt and pivot tensioner pulley outboard.
12. Retighten tensioner lock bolt. NOTE: Mark timing belt for rotation if it is being reused.
    
13. Remove timing belt.

To Install:
Crankshaft match marks

1. Align marks on timing belt pulley and pump body. Camshaft pulley alignment marks
   
   
2. Align marks on camshaft pulleys with alignment marks on seal plate.
3. Install timing belt. NOTE: No looseness should exist on the tension side and at the camshaft pulleys.
   
4. Loosen tensioner lock bolt.
5. Turn crankshaft 2 revolutions in direction of rotation and check that timing marks are still in alignment.
6. Tighten timing belt tension lock bolt to 27-38 ft lb (32-52 Nm).
7. Apply a force of 22 lbs to timing belt between camshaft sprockets.
   • Belt deflection should measure 0.30-0.33 in (7.5-8.5 mm)
   NOTE: Replace tensioner spring if timing belt deflection is excessive.
   Timing Belt Installation
   
   
8. Install lower timing belt cover.
9. Install upper timing belt cover.
10. Install power steering drive belt and adjust belt tension.
11. Install fan pulley.
12. Install generator drive belt and adjust belt tension.
13. Install A/C drive belt and adjust belt tension.
14. Install splash guard.
15. Install fan and fan shroud.
16. Install 4 fan bolts. Tighten to 24 ft lb (33 Nm).
17. Install fan shroud mounting bolts.
18. Install fresh air duct.
19. Connect hose to resonance chamber.
20. Connect battery negative cable.

hi,try to adjust the belt tension, find 3 fastening loosen,with help of fri bar pull,then adjust the tension or replace with small diameter if possible,ty

REMOVAL & INSTALLATION

See Figures 1 and 2


Fig. Fig. 1: Rear terminal alternator


Fig. Fig. 2: Side terminal alternator

1. Open the hood and disconnect the battery ground cable.
2. Remove the adjusting arm bolt.
3. Remove the alternator through-bolt. Remove the drive belt from the alternator pulley and lower the alternator.

Some engines are equipped with a ribbed, K-section belt and automatic tensioner. A special tool must be made to remove the tension from the tensioner arm. Loosen the idler pulley pivot and adjuster bolts before using the tool. See the accompanying illustration for tool details.

1. Label all of the leads to the alternator so that you can install them correctly and disconnect the leads from the alternator.
2. Remove the alternator from the vehicle.
3. To install, reverse the above procedure. Torque the pivot bolt to 58 ft. lbs.; the adjusting bolt to 25 ft. lbs.; the wire terminal nuts to 60-90 inch lbs.

BELT TENSION ADJUSTMENT

The fan belt drives the alternator and water pump. If the belt is too loose, it will slip and the alternator will not be able to produce it rated current. Also, the water pump will not operate efficiently and the engine could overheat.
Check the tension of the belt by pushing your thumb down on the longest span of the belt, midway between the pulleys. Belt deflection should be approximately 1 / 2 inch; (13mm).To adjust the belt tension, proceed as follows:

1. Loosen the alternator mounting bolt and the adjusting arm bolts.
2. Apply pressure on the alternator front housing only, moving the alternator away from the engine to tighten the belt. Do not apply pressure to the rear of the cast aluminum housing of an alternator; damage to the housing could result.
3. Tighten the alternator mounting bolt and the adjusting arm bolts when the correct tension is reached.

It should be either just above the air conditioning compressor, or on the opposite side. It will have two wires coming out - a red wire ( 12 volt plus) and a black ground wire. The a/c compressor has metal fittings and rubber hoses as well as a clutch. No need to touch the a/c compressor. I changed alternators on my 300D models and 300 SD. They are very much the same. You will need to loosen the adjustment slider and physically slide the alternator to loosen the belt. Remove the wires from the alternator - probably a plug at the rear. If the car has a single serpentine belt the problem is more complex because so many units run off the same belt, including the water pump, fan and a/c compressor. Restoring proper tension is critical. The alternator swings in a vertical arc on a long bolt on the bottom or side that runs from front to rear.  Replacement is not difficult - hold the new unit in place while you insert and tighten the long bolt, then reposition the tension slider and tighten that bolt. The tension needs to be correct or else the belt will slip and squeal and your battery will not charge properly. You may need a crowbar the achieve the right tension while you tighten the tension slide. Instead of replacing the alternator altogether, why not just replace the brush on a round plate at the rear. Most alternator failures involve worn brushes. The rebuilders simply replace them and sell a "rebuilt" unit. Make sure you can get brushes and/or a brush assembly before you start.. Loosen the tension but do not remove the alternator. Remove the two small nuts that hold the brush assembly at the rear and slide it off. Replace with the new one.  Be sure you retract the brushes so they will slip back over the armature, and align with the retaining screws. Tighten them. Re-tension the belt and you're home free. I have done this on the road when necessary. Easier and cheaper than changing the entire alternator.