Belt tension too loose

no adjustment, proper routing? if so tensioner need replacement.

1989 Belts

• INSPECTION
• ADJUSTING
• REMOVAL & INSTALLATION

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INSPECTION

All Models
Belt tension is very important, as a belt that is too tight will put too much stress on the bearings of the components it drives, causing them to wear out prematurely. A belt that is too loose will slip, causing (1) the belt to wear out quickly due to friction heat, and (2) inefficient alternator, air pump, cooling fan or air conditioner operation because much of the turning power supplied by the main drive pulley is lost.
The belts should be inspected and/or adjusted at 2,000 miles (3,221 km) and then every 4,000 miles (6,441 km). First, make sure that the belt is properly positioned in the pulley. Check the pulleys for damage. Inspect the belts for cracks and signs of fraying. These usually develop on the inner surface and extend into the backing or outer surface of the belt. Check also for glazing, a completely smooth appearance which indicates slippage. A belt that is in good shape will have a slightly grainy appearance like cloth. Replace belts that show cracks or glazing.
Check belt tension. Apply pressure with your thumb at the mid-point between two pulleys, and the belt should stretch or deflect about 1 / 4 - 1 / 2 in. (6-13mm). If the belt is too tight or too loose, adjust/replace as necessary.

ADJUSTING

Except RX-7
See Figures 1, 2 and 3
To adjust belts, first locate the mounting bolt on the air pump or alternator (each has its own belt and adjusts to permit that belt to be tensioned correctly). This bolt attaches the unit to the engine and has a nut on the end. Put a wrench on either end and loosen the bolt until there is practically no tension on it. Then, loosen the adjusting bolt, which is located on the opposite side of the unit and which passes through a slot. Pull the alternator or air pump away from the engine and tighten the adjusting bolt just enough to hold the unit while you check tension. Repeat the adjustment procedure until the belt deflects the proper amount, then fully tighten the adjusting and mounting bolts. Avoid too much belt tension or overtightening of bolts. A new belt should be tensioned just slightly more (about 0.4 in. or 10mm deflection) and checked after several hundred miles of operation to make sure that tension is still adequate. (Tension is lost very rapidly until a new belt is broken in.)

Fig. Fig. 1: Some engines utilize an idler pulley with a locknut at its center

Fig. Fig. 2: After loosening the idler adjuster locknut, turn the adjusting bolt clockwise to increase belt tension or counterclockwise to decrease it

Fig. Fig. 3: On some GLC engines equipped with power steering, the pump pulley uses a slotted adjusting bar, adjusting bolt and locknut to adjust belt tension
Late model GLCs, 323s, 626s, MX-6s and 929s may use an adjusting bolt on either the idler pulley (a pulley which is not directly associated with any of the accessories) or on the power steering pump itself. This bolt makes adjustment much easier because you don't have to hold the accessory under a great deal of tension while tightening the mounting bolts.
On models where the idler pulley has a locknut at its center, simply loosen the locknut, then turn the adjusting bolt clockwise to increase belt tension or counterclockwise to decrease it or remove the belt. Do not forget to retighten the locknut when tension is correct, or vibration may cause it to fall off. Recheck the tension with the locknut tightened and readjust if necessary.
To adjust the power steering pump pulley on the GLC, loosen the slotted adjusting bar bolt, the mounting bolt across from it, and the locknut at the bottom of the adjusting bolt. Turn the adjusting bolt counterclockwise to remove the belt or reduce tension, and clockwise to increase it. When tension is correct, tighten the adjusting bolt locknut, adjusting bar bolt, and pump mounting bolt.
On 626, MX-6 and 929 models with a 4-ridge or 5-ridge ribbed type V-belt driving both the air conditioner and power steering pump, belt tension is much greater. With a used belt, deflection should only be about 1 / 4 in. (6.35mm).
RX-7
See Figures 4, 5 and 6
The RX-7 may be equipped with as many as three or four separate drive belts. The belts are arranged at the front of the engine and drive the cooling fan/water pump, alternator, power steering pump, emission control air pump and air conditioner compressor (if so equipped).

Fig. Fig. 4: Checking belt tension on 1979-85 RX-7
Check the tension of each belt at the arrows numbered 1, 2, 3 and 4 (depending on year) shown in the illustration. Press on the belt with your thumb using moderate pressure (about 22 lbs.). The belts should give or deflect the amounts shown in the chart.

Fig. Fig. 5: Checking belt tension on 1986-89 RX-7

Fig. Fig. 6: RX-7 belt deflection limits
Use the following appropriate procedure and illustration to make drive belt adjustment(s).
ALTERNATOR AND AIR PUMP
See Figure 7

1. Slightly loosen the stationary pivot bolt on the alternator or air pump.
2. Loosen the adjusting bolt.
3. Using a piece of wood (tool handle, etc.) as a prybar, move the alternator or air pump outward or inward until the proper deflection is obtained.

Fig. Fig. 7: Adjusting alternator drive belt tension on 1986-89 RX-7
When prying on the alternator or air pump, make sure the prybar is anchored against the engine case and not against a component (distributor cap, etc.) which could break.

1. Tighten the adjusting bolt. Remove the prybar and tighten the pivot bolt.

AIR CONDITIONING COMPRESSOR AND POWER STEERING PUMP
See Figures 8 and 9

1. Loosen the locknut on the idler pulley, if so equipped.
2. Turn the adjusting bolt until the proper tension is reached.

Fig. Fig. 8: Adjusting air conditioning compressor drive belt tension on 1986-89 RX-7

1. Tighten the locknut and recheck the belt tension.

Fig. Fig. 9: Adjusting power steering pump drive belt tension on 1986-89 RX-7

REMOVAL & INSTALLATION

All Models

1. Loosen the accessory being driven and move it on its pivot point to free the belt.
2. Remove the belt. If an idler pulley is used, it is often only necessary to loosen the idler pulley to provide enough slack to remove the belt.

To install:

1. After the new belt is in place and properly tensioned, start the engine and allow it to run for about five minutes to seat the new belt.
2. Stop the engine and recheck the belt tension. Adjust as necessary.

On engines with many driven accessories, other belts may have to be removed to access the one being replaced.

INSPECTION

Inspect the belts for signs of glazing or cracking. A glazed belt will be perfectly smooth from slippage, while a good belt will have a slight texture of fabric visible. Cracks will usually start at the inner edge of the belt and run outward. All worn or damaged drive belts should be replaced immediately. It is always best to replace all drive belts at one time, as a preventive maintenance measure, during this service operation.

CHECKING TENSION AND ADJUSTMENT

See Figure 1
The belt tension on most driven components is adjusted by moving the component (alternator, power steering pump etc.) within the range of a slotted bracket. Some brackets (toothed) use a rack and pinion mechanism which moves the alternator side-to-side to adjust the belt tension. With this configuration, no prying tools are required. On Quantum (except 5 cylinder) and Fox models, the air conditioner compressor drive belts are adjusted by varying the number of discs (shims) between the halves of the crankshaft pulley. Before adjusting the belt tension on any engine, look at the mounting and determine what kind of bracket is used.
To check belt tension, push in on the drive belt about midway between the crankshaft pulley and the driven component. If the belt is less than 39.4 in. (1m) long, it should deflect between 0.80-0.120 in. (2-5mm). For longer belts, it should deflect between 0.40-0.060 in. (10-15mm). Belt size is usually printed on the back side of the belt. If it can't be read, it's probably time to replace it.

Fig. Fig. 1: To check belt tension, push in on the drive belt about midway between the crankshaft pulley and the driven component
Slotted Brackets
See Figures 2, 3 and 4

1. Loosen the adjustment nut/bolt in the slotted bracket. Slightly loosen the pivot bolt.
2. Pull (don't pry) the component outward to increase tension. Push inward to reduce tension. Tighten the adjusting nut/bolt and the pivot bolt.

Fig. Fig. 2: Alternator mounting with slotted brackets

1. Components, such as the power steering pump and some air conditioner compressors, may be mounted with a double slotted adjusting bracket using a threaded bolt and locknut to adjust and maintain tension. Loosen the locknut(s) and slightly loosen the bolt(s) in the slotted groove(s). Turn the threaded adjustment bolt(s) in or out to gain correct tension. Tighten locknut(s) and slotted bracket bolt(s).
2. Recheck the drive belt tension, readjust if necessary.

Fig. Fig. 3: Some components use a double slotted adjusting bracket with a threaded bolt and locknut to adjust and maintain tension. Loosen the locknut (shown) before adjusting the tension bolt

Fig. Fig. 4: An extension is helpful when adjusting the tension bolt. Be sure to loosen the nut/bolt on the rear slotted bracket first
Toothed Brackets
See Figures 5 and 6

1. Loosen the tension bolt and the alternator pivot bolt. These bolts should be loosened until the alternator swings freely under its own weight.

Fig. Fig. 5: Loosen the tension bolt (shown) and the alternator pivot bolt until the alternator swings freely under its own weight

1. Adjust the V-belt by turning the nut on the tension bolt while checking the belt deflection with your thumb.
2. Once the proper tension is achieved, tighten the tension bolt to 26 ft. lbs. (35 Nm). Tighten the pivot bolt to 15 ft. lbs. (20 Nm).
3. Recheck the drive belt tension, readjust if necessary.

Fig. Fig. 6: Adjust the V-belt by turning the nut on the tension bolt
Split Pulley
See Figure 7
On Quantum (except 5 cylinder) and Fox models, the air conditioner compressor drive belts are adjusted by varying the number of discs (shims) between the halves of the crankshaft pulley.

1. Remove the nuts/bolts securing the tensioner plate and crankshaft pulley halves.
2. Add or remove the amount of spacer discs between the pulley halves until the belt tension is correct.

Fig. Fig. 7: Belt adjusting shims on Quantum (except 5 cylinder) and Fox models. Extra shims are stored behind the tensioner plate on Fox and turbo diesel Quantums (shown)
If there are any shims left over, do not throw them away. On Fox and turbo diesel Quantum models, store the extra shims in front of the split pulley (behind the tensioner plate). On Quantums with 4 cylinder gas engines, store the extra shims behind the split pulley (in front of the crankshaft hub).

1. Secure the pulley halves. Torque the pulley nuts or bolts to 15 ft. lbs. (20 Nm).

REMOVAL & INSTALLATION

If a belt must be replaced, the driven unit must be loosened and moved to its extreme loosest position (usually by moving it toward the center of the motor). After removing the old belt, check the pulleys for dirt or built-up material which could affect belt contact. Carefully install the new belt, it may appear to be just a little too small to fit over the pulley flanges. Fit the belt over the largest pulley (usually the crankshaft pulley at the bottom center of the motor) first, then work on the smaller one(s). Gentle pressure in the direction of rotation is helpful. Some belts run around a third or idler pulley, which acts as an additional pivot in the belt's path. It may be possible to loosen the idler pulley as well as the main component, making your job much easier. Depending on which belt(s) you are changing, it may be necessary to loosen or remove other interfering belts to get at the one(s) you want. Some models have a front engine mount installed through the air conditioner compressor belt circle. Support the engine and remove the mount prior to belt removal and installation.
When buying replacement belts, remember that the fit is critical according to the length of the belt, the width of the belt, the depth of the belt and the angle or profile of the V shape (always match up old belt with new belt if possible). The belt shape should exactly match the shape of the pulley; belts that are not an exact match can cause noise, slippage and premature failure.
After the new belt is installed, adjust it for proper tension. This is sometimes a three or four-handed job; you may find an assistant helpful. Make sure that all the bolts you loosened are retightened and that any other loosened belts also have the correct tension. A new belt can be expected to stretch a bit after installation so be prepared to re-adjust your new belt.
After installing a new belt, run the engine for about 5 minutes and then recheck the belt tension.

ADJUSTMENT

Inspect the drive belt(s) every 30,000 miles or 24 months. Determine the belt tension at a point halfway between the pulleys by pressing on the belt with moderate thumb pressure. If the deflection is found to be too much or too little, perform the tension adjustments.
On some Acura models it will be necessary to work from beneath the vehicle when servicing the accessory drive belts.
Before adjusting, inspect the belt to see that it is not cracked or worn. Be sure that its surfaces are free of grease and oil. If contamination is present, belt replacement is recommended.

1. Push down on the belt halfway between pulleys with a force of about 20 lbs. The belt should deflect: 0.16-0.41 in. (4-11mm)-on Integra and 0.22-0.45 in. (5.5-11.5mm) on all other models.
2. Adjust the belt tension by loosening the adjusting bolts.
3. Next loosen any mounting bolts and/or nuts that may hinder adjustment.

3.0CL models have automatic tensioners therefore no belt adjustment is required.

1. To adjust the alternator belt tension on Integra, loosen the adjustment lock bolt and move the alternator with a prybar positioned against the front of the alternator housing.

WARNING Do not apply pressure to any other part of the alternator or damage may occur.

1. To adjust the tension on all other accessory drive belts (all Acura models except 3.0CL), loosen the adjustment lock bolt and turn the adjusting bolt (if applicable) as required.

Do not over tighten any of the belts. Damage to the pulley's bearings may result.

1. After obtaining the proper tension, tighten the adjustment lock bolt.
2. Tighten all other bolts and/or nuts that were loosened in the adjustment process.

See Figures 6 through 13

Fig. Fig. 6: Location of adjusting mechanism for the A/C belt on the Integra's 1.8L engine

Fig. Fig. 7: Alternator belt adjustment-Integra

Fig. Fig. 8: Power steering belt adjustment-Integra

Fig. Fig. 9: A/C compressor belt adjustment-Integra

Fig. Fig. 10: Alternator belt adjustment-3.2L engine

Fig. Fig. 11: Power steering belt adjustment-3.2L engine

Fig. Fig. 12: A/C compressor belt adjustment-3.2L engine

Fig. Fig. 13: Belt routing and alternator belt adjustment-2.5L engine

REMOVAL & INSTALLATION

Many Acura models are equipped with a theft deterrent audio system. Make sure you have the necessary code before disconnecting the battery.

1. Disconnect the negative battery cable.
2. Loosen the driven accessory's pivot and mounting bolts.

If removing the alternator belt on a 3.0CL, pull back on the belt tensioner with a commercially available tool.

1. Remove the belt.
2. Install the belt by moving the accessory toward or away from the engine until the tension is correct. You can use a wooden hammer handle, or broomstick, as a lever, but do not use anything metallic, such as a prybar. Certain models may utilize an adjusting bolt to do this work for you. Simply loosen the mounting bolt and turn the adjuster.

On 3.0CL pull back on the tensioner to install the belt, the tension is automatically set.

1. Tighten the bolts and recheck the tension. If new belts have been installed, run the engine for a few minutes, then recheck and readjust as necessary

The power steering belt tensioner may be out of adjustment and the belt slips more under the extra load when you turn. Apparently you don't have one of the serpentine belts with a spring tensioner; when these fail the belt usually comes off very quickly. Examine the belt carefully - if the sides of the belt are shiny-slick from all of the slipping, replace the belt.

It's also a good idea to check the power steering fluid. This isn't something to ignore; a sudden or erratic change in steering wheel force in an emergency situation could be catastrophic.

find out WHY belt is loose??? water pump bad? belt tensioner bad? my bets are belt tensioner.

If you're talking about the little tool that you test the belt tension with, just use your finger to test the deflection of the belt. It should move up about a half inch or so when you push up with your finger with about 10 pounds of pressure. If it feels like you would adjust a chain final drive, it's a bit too loose.

Good Luck
Steve

You don't adjust the tension. The tensioner on that serpentine belt is spring loaded and never needs adjustment.
On a 2001 with normal miles (~125k), you should be on your second tensioner pulley and your third serpentine belt by now.

Either front roller may need to be replaced or the motor drive belt may need to be adjusted. This problems are caused when a walking belt is worn out and in need of replacement. Too much tension can cause bearing failure in the motor and the front roller and front roller pulley failure.

Motor drive belt adjustment: The motor drive belt is adjusted independently from the walking belt. Some newer models have an auto tensioner which is a lever that has a wheel that puts pressure on the drive belt and a spring on the other end that automatically loads the belt to the proper tension. You should not adjust these since they are preset. Tension can be affected slightly by adjusting the tension of the walking belt but if you have a slipping problem, the drive belt will require replacement. If your drive belt is too loose, it will slip on the front roller pulley or the motor pulley. If it is too tight, it will increase your amp draw to the point that you may have an electronics or motor problem. Due to this, it is better to be on the safe side and replace a drive belt rather than risk over tightening it.

If you are looking at the belt while the vacuum is in the upright and locked position, the belt will be loose. The idler removes tension so the brush doesn't spin while you walk away and put heat marks in the carpet. Hit the lever that allows you to move the handle low, like you are vacuuming under the bed, and the belt gets tight.