How to remove automatic tensioner pulley in ML430 mercedese?

IF YOU HAVE THE TENSIONER PULLEY JUST PLACE WRENCH ON CENTER TENSIONER PULLEY BOLT.TURN TENSIONER PULLEY BOLT CLOCKWISE TO REMOVE THE BELT.IF YOU HAVE THE AUTOMATIC TENSIONER YOU NEED A BREAKER BAR PLACE IT IN THE TENSIONER .PUSH DOWNWARD FORWARD ON BREAKER BAR AND REMOVE THE DRIVE BELT. TO GET TO BELT TENSIONERS. YOU HAVE TO REMOVE THE WHEEL SPLASH SHIELD.

I cant find a diagram however i can tell you how it goes. Starting at the alternator the belt goes completely around alternator (ridge side to pulley). pulley then over the water pump pulley (smooth side to the pulley), then down to the right around the tensioner pulley (smooth side to the pulley), then back to the left up and over the crank pulley (ridge side to the pulley), then to the right around the ac compressor (ridge side to the pulley), then up over the power steering pulley (ridge side to pulley) and then finally to the left over the idler pulley. have a good day.

there is no spring tensioner on some of the 3.0 engines. See instructions below. I will paste a pic on the version that DOES have a tensioner at the bottom of this post.

3.0L Engine-Except SHO
ALTERNATOR BELT WITHOUT AUTOMATIC TENSIONER

1. Loosen the adjusting arm and pivot bolts.
2. Turn the alternator belt adjusting screw counterclockwise until the old belt can be removed.
3. Remove the belt.

To install:

1. Install the new belt over the pulleys. Check that all the V-grooves make proper contact with the pulleys.
2. Adjust the belt tension, then tighten the adjusting arm and pivot bolts.

3.0L SHO Engine
ALTERNATOR BELT
See Figure 2

1. Loosen the nut in the center of the idler pulley.
2. Loosen the idler adjusting screw until the old belt can be removed, then remove the belt.

To install:

1. Install the new belt over the pulleys in proper contact with the pulleys.
2. Adjust the new belt to specifications as follows: Turn the idler pulley nut to the right to tighten the belt to a specification of 220-265 lbs. (980-1180 N). Torque the idler pulley nut to 25-37 ft. lbs. (34-50 Nm).

POWER STEERING AND AIR CONDITIONING BELT
See Figure 2

1. Remove the alternator belt.
2. Loosen the nut on the tensioner pulley.
3. Turn the belt adjusting screw on the tensioner counterclockwise until the belt can be removed, then remove the belt.

To install:

1. Position the new belt over the proper pulleys, making sure the V-grooves are properly seated.
2. Install the alternator belt.
3. Adjust the power steering and air conditioning belt to a specification of 154-198 lbs. (690-980 N) with a belt tension gauge.
4. Adjust the alternator belt.

3.0L Engine (Except SHO) and 3.8L Engine
VEHICLES THROUGH 1993 WITH AUTOMATIC TENSIONER
See Figures 4 and 5

1. Insert a 1 / 2 in. breaker bar into the square hole in the tensioner.

On the 3.8L engine, the tensioner has a1/2in. square hole cast into the rear of the tension arm directly behind the pulley. On the 3.0L engine, the1/2in. square hole is cast into the spring housing on the front of the tensioner.

1. Rotate the tensioner clockwise and remove the belt.

Fig. Fig. 5: 3.8L belt schematic-1993 shown

To install:

1. Install the drive belt over all the pulleys, except for the alternator pulley on the 3.0L engine for vehicles through 1992, or the idler pulley for 1993 3.0L vehicles.
2. Rotate tensioner counterclockwise and install the belt over the alternator pulley. Make sure that all the V-grooves make proper contact with the pulleys.
3. On the 3.0L engine, install the alternator belt for vehicles through 1992.
4. For 1993 3.0L vehicles, install the drive belt over the idler pulley.

The belt routing is often found on a sticker, under the hood. But, the best I can do is instructions on how to change the belts, step by step:
REMOVAL & INSTALLATION 1.8L Engines ALTERNATOR AND WATER PUMP BELT

1. Riase the front of the car and support it with safety stands.
2. Loosen the alternator adjusting bolt.
3. If necessary, remove the power steering drive belt .
4. Loosen the alternator mounting bolt.
5. Remove the alternator and water pump drive belt. To install:
   
6. Install the alternator and water pump drive belt.
7. Adjust the belt tension.
8. If removed, install the power steering pump belt.
9. Tighten the alternator adjusting bolt to 14–19 ft. lbs. (19–25 Nm).
10. Tighten the alternator mounting bolt to 27–38 ft. lbs. (37–52 Nm).
11. Lower the vehicle.

POWER STEERING PUMP BELT

1. Raise and safely support the vehicle.
2. Loosen the power steering pump mounting bolt and nuts.
3. Remove the drive belt. To install:
   
4. Install the belt and adjust the tension.
5. Tighten the power steering pump mounting nut, located near the adjusting bolt, to 27–38 ft. lbs. (37–52 Nm).
6. Tighten the pump mounting bolt behind the pulley to 27–40 ft. lbs. (36–54 Nm), and the remaining pump mounting nut to 23–34 ft. lbs. (31–46 Nm).
7. Lower the vehicle.

1.9L and 2.0L SOHC Engines

1. Insert a 3?8 in. drive ratchet or a breaker bar in the hole on the automatic tensioner, then pull the tool toward the front of the vehicle.
2. While releasing the belt tension, remove the drive belt from the tensioner pulley and slip it off the remaining accessory pulleys. Fig. 1: Insert a 3?8 in. drive ratchet or breaker bar into the hole of the automatic tensioner
   Fig. 2: Pull the breaker bar or ratchet toward the front of the vehicle to relieve belt tension
   Fig. 3: Once the tension has been released, remove the belt from the pulleys and the vehicle
   To install:
   
3. Position the drive belt over the accessory pulleys.
4. Insert the 3?8 in. drive ratchet or breaker bar into the hole of the automatic tensioner, then pull the tool toward the front of the vehicle.
5. While holding the tool in this position, slip the drive belt behind the tensioner pulley and release the tool.
6. Remove the tool from the automatic tensioner.
7. Check that all V-grooves make proper contact with the pulley.

2.0L DOHC Engines

1. Raise the car and safely support it with jackstands.
2. Use a 13mm wrench to rotate the tensioner clockwise.
3. Remove the drive belt from the pulleys. To install:
   
4. Position the belt on the pulleys.
5. Use a 13mm wrench to rotate the tensioner clockwise.
6. Route the belt as shown in the illustration and release the tensioner.
7. Lower the car.
8. Run the engine for a few minutes to seat the belt in the pulley grooves.

4.7L or 5.9L and it should be listed on a sticker somewhere in the engine compartment.

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Drive Belt Removal & Installation 3.7L, & 4.7L Engines To Remove:

1. Before servicing the vehicle, refer to the precautions at the beginning of this section.
2. Disconnect negative battery cable.
3. Rotate tensioner until it stops.
4. Remove belt and slowly rotate the tensioner back to its free position.

To Install:

1. Install new belt and route around all pulleys except idler pulley.
2. Rotate the tensioner arm until it stops.
3. Route the belt around the idler pulley and slowly let the tensioner rotate back to its free position.

3.9L, 5.2L, & 5.9L Engines To Remove:
NOTE: Check the belt routing label, located in the engine compartment, for the most current belt routing schematic.
CAUTION
Do not attempt to check tension with a belt tension gauge on vehicles equipped with an automatic belt tensioner.

1. Before servicing the vehicle, refer to the precautions at the beginning of this section.
2. Attach a socket wrench to the pulley mounting bolt of the automatic belt tensioner and rotate the tensioner assembly clockwise until tension is relieved.
3. Remove or disconnect the following:
   • Belt from idler pulley
   • Belt from vehicle

To Install:

1. Position drive belt over all pulleys except idler pulley.
2. Attach a socket wrench to automatic belt tensioner and rotate the tensioner assembly clockwise.
3. Install belt over idler pulley, allow tensioner to rotate back into place, and remove the wrench.

Disconnect battery earth lead. Do not turn crankshaft or camshaft when timing belt removed. Remove spark plugs to ease turning engine. Turn engine in normal direction of ratation unless otherwise stated, Support engine. Remove, engine mounting, auxilliaty drive belts. Water pump pulley 1. Crankshaft pulley bolts 21. crankshaft pully 2. timing belt covers 3. Turn crankshaft to TDC on No 1 cyclinder. Ensure crankshaft sprocket, camshaft sprocket, oil pump sprocket and balancer shaft sprocket timing marks aligned. Timing marks on camshaft sprockets should align with cylinder head upper face. Dowel pins on camshaft sprockets should face upwards. Slacken tensioner bolt. Move tensioner away from belt and lightly tighten bolt. Remove, automatic tensioner unit bolts. Automatic tensioner unit. Timing belt, crankshaft centre bolt, crankshaft sprocket. Crankshaft sprocket guide washer. Slacken blancer shaft belt tensioner bolt. Move tensioner away from belt and lightly tighten bolt. Remove balancer shaft belt.

Installation
Ensuring timing marks arligned. Note timing marks on camshaft sprockets should align with cylinder head upper face. Exhaust sprocket mark is on recess, but inlet sprocket mark is on tooth. Note: to check oil pump sprocket positioned correctly, removing blanking plug from cylinder block. Insert 8mm diameter Phillips srcrewdriver in hole. Ensure screwdriver is inserted 60mm from face of cylinder block. if screwdriver can only be inserted 20mm: turn oil pump sprocket 360°. Insert screwdriver again. Fit balancer shaft belt in anti-clockwise direction, starting at crankshaft sprocket. Slacken balancer shaft belt tensioner bolt. Turn tensioner clockwise to tension belt. Tighten bolt to 15-22Nm. Apply thumb pressure to belt. Belt should deflect 5-7 mm. If not repeat tensioning procedure. Install crankshaft sprocket guide washer, crnakshaft sprocket. Tighten crankshaft cente bolt. Tighten torque:110-130 Nm. Note ensure crankshaft sprocket guide washer is fitted correclty. Oil treads and contact face of crankshaft body before fitting. Check tensioner body for leakage or damage replace if necessary. Check pushrod protrusion is 12mm. If not replace automatic tensioner unit. Slowly compress pushrod into tensioner body until holes aligned. Resistance should be felt. Place flat washer under tnesioner body to avoid damage to body end plugs. Retain pushrod with suitable pin through hole in tensioner body. install automatic tensioner unit to cylinder block. Tighten bolts to 22-27Nm. Fit timing belt in anti-clockwise direction, starting at the tensioner pulley. Slacken tensioner pulley bolt. Turn tensioner pully clockwise to temporarily tension belt. Tighten bolts to 43-45Nm. Turn crankshaft slowly 1/4 turn anti-cockwise. Turn crankshaft clockwise until timing marks alligned. Slacken tensioner pully bolt. Fit tool to tensioner pulley. Tool No 09244 28100. Apply clockwise torque of 2,6-2,8 Nm to tensioner pulley. Tighten bolt to 43-45Nm. Insert special tool in timing belt rear casing. Tool no 09244-28000. Screw in tool until pin can be removed from automatic tensioner unit. Remove special tool. Tool nr 09244-28000. turn crankshaft two turns clockwise. Wait 15 minutes. Ensure timing marks aligned. Check extended length of pushrod is 3,8-4,5mm. Install components in reverse order of removal. Tighten crankshaft pulley bolts, Tighten torque 20-30Nm

Installation > 5.9L Diesel Engine 5.9L Diesel Engine
WARNING Do not attempt to check belt tension with a belt tension gauge on vehicles equipped with an automatic belt tensioner.

Drive belts on diesel engines are equipped with a spring loaded automatic belt tensioner. This belt tensioner will be used on all belt configurations, such as with or without air conditioning.

1. Depending on the year of the vehicle, a 3/8 inch or 1/2 inch square hole is provided in the automatic belt tensioner. Attach a 3/8 inch or 1/2 inch drive-long handle ratchet to this hole.
   
2. Rotate ratchet and tensioner assembly clockwise (as viewed from front) until tension has been relieved from belt.
   
3. Remove belt from water pump pulley first.
   
4. Remove belt from vehicle.
   

To install:

WARNING When installing the accessory drive belt, the belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. The correct belt with correct length must be used. Position drive belt over all pulleys except water pump pulley.

1. Attach a 1/2 inch ratchet to tensioner.
   
2. Rotate ratchet and belt tensioner clockwise. Place belt over water pump pulley. Let tensioner rotate back into place. Remove ratchet. Be sure belt is properly seated on all pulleys.
   

RETAIN PUSHROD WITH SUITABLE PIN THROUGH HOLE IN TENSIONER BODY.
INSTALL AUTOMATIC TENSIONER UNIT TO TENSIONER BLOCK. TIGHTEN BOLTS TO 22-27.
FIT TIMING BELT IN ANTI-CLOCKWISE DIRECTION, STARTING AT TENSIONER PULLEY.
SLACKEN TENSIONER PULLY BOLT. TURN TENSIONER PULLEY CLOCKWISE TO TEMPORARILY TENSION BELT. TIGHTEN BOLT TO 43-45NM.
TURN CRANKSHAFT SLOWLY 1/4 TURN ANTI CLOCKWISE.
TURN CRANKSHAFT CLOCKWISE UNTIL TIMING MARKS ALIGNED.
SLACKEN TENSIONER PULLEY BOLT. FIT TOOL TO TENSIONER PULLEY.
APPLY CLOCKWISE TORQUE TO TENSIONER PULLEY. TIGHTEN BOLTS.
INSERT SPECIAL TOOL IN TIMING BELT REAR CASING.
SCREW IN TOOL UNTIL PIN CAN BE REMOVED FROM AUTOMATIC TENSIONER.
REMOVE SPECIAL TOOL.
TURN CRANCSHAFT TWO TURNS CLOCKWISE. WAIT 15 MINUTES.
ENSURE TIMING MARKS ALIGNED.
CHECK EXTENDED LENGTH OF PUSHROD IS 3.8 - 4.5MM
RE-ASSEMBLE

go to this web site for a diagram and step by step instructions:
autozone.com

5.9L DIESEL
The 5.9L diesel engine accessory drive system (with a/c) consists of :

1. Generator Pulley (1)
2. Water Pump Pulley (2)
3. Idler Pulley (3)
4. Power Steering Pump Pulley (4)
5. Radiator Fan Pulley (5)
6. Crankshaft Pulley (6)
7. Automatic Tensioner (7)
8. A/C Compressor Pump Pulley (8)

CAUTION: When installing the accessory drive belt, the belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. Refer to or for correct engine belt routing. The correct belt with correct length must be used.
1. Position drive belt over all pulleys except water pump pulley. 2. Attach a 1/2 inch ratchet to tensioner.


The 5.9L diesel engine accessory drive system (without a/c) consists of :

1. Generator Pulley (1)
2. Water Pump Pulley (2)
3. Idler Pulley (3)
4. Power Steering Pump Pulley (4)
5. Radiator Fan Pulley (5)
6. Crankshaft Pulley (6)
7. Automatic Tensioner (7)

3. Rotate ratchet and belt tensioner clockwise. Place belt over water pump pulley. Let tensioner rotate back into place. Remove ratchet. Be sure belt is properly seated on all pulleys.