How do i loosing up the tension belt's to replace the water pump??

Belt Tension-er or Belt Idler. Alternator, Ac or Power steering pump bearings.

A water pump would not have bands.
If the water pump pulley is loose, the bearing may have failed. If that is the case, the water pump would need to be replaced.
If the serpentine belt is loose, the tensioner may have failed.

1. Drain the cooling system until the coolant is below the level of the water pump.
2. Loosen the water pump pulley bolts.
3. Rotate the drive belt tensioner to release the tension on the drive belt.
4. Remove the drive belt from the right idler pulley.
5. Carefully release the drive belt tensioner spring tension.
6. Remove the water pump pulley bolts.
7. Remove the water pump pulley.
8. Remove the water pump bolts.
9. Remove the water pump.
10. Remove the water pump gasket.
11. Clean the water pump mating surfaces.

To install:

Fig. Remove the mounting bolts (3) to remove the water pump (1) and gasket (2).

1. Install the water pump gasket (2).
2. Install the water pump (1).
3. Install the water pump bolts (3). Tighten the bolts to 10 Nm (89 inch lbs.).
4. Install the water pump pulley. Loosely install the pulley bolts.
5. Insure the drive belt is properly centered on all the pulleys except the right idler puller.
6. Rotate the drive belt tensioner away from the drive belt.
7. Install the drive belt to the right idler pulley.
8. Release the tensioner allowing the drive belt tensioner to come in contact with the drive belt.
9. Inspect the drive belt to insure the belt is properly centered on all the pulleys.
10. Tighten the water pump pulley bolts. Tighten the bolts to 25 Nm (18 ft. lbs.).
11. Fill the cooling system.
12. Inspect the cooling system for leaks.

the water pump is under the timing chain cover. if your serpentine belt is loose, that is the belt you can see, then your tensioner is shot. you can buy a new tensioner for about 50 bucks at a parts store. search on www.youtube.com for video directions on how to replace it. if your serpentine belt has not been changed this is a good time to do that as well as it has to come off. replacement of the tensioner and belt is done via a service panel behind the right front wheel.

Yes, the serpentine belt runs all those pumps. Water , power steering, alternator ,ect. If its loose have the tensioner and belt checked out and replaced.

Kind of a vague question here. I am assuming you are speaking of the pulley that is attached to the tensioner is bent. Either way I would suggest in replacing the tensioner. They have just he pulley you can take off your tensioner and rebuild it, but it is easier for the cost, and as a point of preventive maintnace to replace the entire tensioner, for the entire tensioner either 4 cyl or 6 is around 96$

If you check tension. If it is loose ..over 1/2" freeplay it is too loose. Tighten. If it feels tight. Then the belt is likely dried out and needs to be replaced... Check tensioner to be sure nothing is froze up. Like water pump or tensioner pulley. Check other belts as well.

Has it just started with cold weather? Does it squeal at first then as the engine is revved, stop squealing.

If so its probably your alternator belt has worked loose and needs tightening. I'd check this out first, if you've not done it before ask a friend with some know how for guidance. But as a guide, there should be about an inch of give when flexed on the longest run between 2 pulleys, if more then probably needs tightening. If more than a couple of years old, replace with a new one.

If it still squeals after tightening/replacing, you could have a faulty water pump bearing or pulley bearing. Either would require replacement to pre-empt catastrophic failure and resultant engine damage.

WATER PUMP
The water pump is bolted directly to the engine timing chain case/cover.

A gasket is used as a seal between the water pump and timing chain case/cover.

If water pump is replaced because of bearing/shaft damage, or leaking shaft seal, the mechanical cooling fan assembly should also be inspected. Inspect for fatigue cracks, loose blades, or loose rivets that could have resulted from excessive vibration. Replace fan if any of these conditions are found. Also check condition of the thermal viscous fan drive. Refer to Viscous Fan Drive in this group.

The water pump can be removed without discharging the air conditioning system (if equipped)

REMOVAL
Disconnect negative battery cable from battery.
Drain cooling system. Refer to Draining Cooling System in this group.
Do not waste reusable coolant. If solution is clean, drain coolant into a clean container for reuse.

The thermal viscous fan drive is attached (threaded) to the water pump hub shaft. Remove fan/viscous fan drive assembly from water pump by turning mounting nut counterclockwise as viewed from front. Threads on viscous fan drive are RIGHT HAND. Using special tool spanner wrench 6958 with adapter pins 8346 and a suitable fan wrench loosen the fan drive Viscous Fan and Fan Drive Do not attempt to remove fan/viscous fan drive assembly from vehicle at this time.
WARNING: CONSTANT TENSION HOSE CLAMPS ARE USED ON MOST COOLING SYSTEM HOSES. WHEN REMOVING OR INSTALLING, USE ONLY TOOLS DESIGNED FOR SERVICING THIS TYPE OF CLAMP, SUCH AS SPECIAL CLAMP TOOL (NUMBER 6094) SNAP-ON CLAMP TOOL (NUMBER HPC-20) MAY BE USED FOR LARGER CLAMPS. ALWAYS WEAR SAFETY GLASSES WHEN SERVICING CONSTANT TENSION CLAMPS.

CAUTION: A number or letter is stamped into the tongue of constant tension clamps. If replacement is necessary, use only an original equipment clamp with matching number or letter.

If water pump is being replaced, do not unbolt fan blade assembly from thermal viscous fan drive.
Remove two fan shroud-to-radiator nuts Fan Shroud Mounting Hardware Do not attempt to remove fan shroud at this time.
Remove fan shroud and fan blade/viscous fan drive assembly from vehicle as a complete unit.
After removing fan blade/viscous fan drive assembly, do not place thermal viscous fan drive in horizontal position. If stored horizontally, silicone fluid in viscous fan drive could drain into its bearing assembly and contaminate lubricant.
Remove accessory drive belt as follows: The drive belt is equipped with a spring loaded automatic belt tensioner. Relax tension from belt by rotating tensioner clockwise (as viewed from front) Automatic Belt Tensioner - When all belt tension has been relaxed, remove accessory drive belt.
Remove lower radiator hose clamp and remove lower hose at water pump.
Remove seven water pump mounting bolts and one stud bolt
CAUTION: Do not pry water pump at timing chain case/cover. The machined surfaces may be damaged resulting in leaks.

Remove water pump and gasket. Discard gasket.
INSTALLATION
Clean gasket mating surfaces.
Using a new gasket, position water pump and install mounting bolts as shown. Water Pump Installation - Tighten water pump mounting bolts to 54 N·m (40 ft. lbs.) torque.
Spin water pump to be sure that pump impeller does not rub against timing chain case/cover.
Connect radiator lower hose to water pump.
Relax tension from belt tensioner Automatic Belt Tensioner - Install drive belt
CAUTION: When installing the serpentine accessory drive belt, belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. Refer to Belt Routing for correct belt routing. Or, refer to the Belt Routing Label located in the engine compartment. The correct belt with correct length must be used.

Position fan shroud and fan blade/viscous fan drive assembly to vehicle as a complete unit.
Be sure the upper and lower portions of the fan shroud are firmly connected. All air must flow through the radiator.
Install two fan shroud-to-radiator nuts Fan Shroud Mounting Hardware
Be sure of at least 25 mm (1.0 inches) between tips of fan blades and fan shroud.
Install fan blade/viscous fan drive assembly to water pump shaft.
Fill cooling system. Refer to Refilling the Cooling System in this group.
Connect negative battery cable.
Start and warm the engine. Check for leaks

1.Most likely alternator belt is not tight enough or need new one.2. A/C-Power steering belt is loose or need new one. 3. Bearing in A/C-Power Steering Tensioner is going bad. 4. Not the water pump unless you are loosing water all the time. Timing belt runs the water pump & you need to tear down the engine. If so ,you would need to replace the timingbelt,tensioners, and maybe the hydraulic tensioner. NOT FOR $300, more like 5-600. Get yourself a Haynes Manual for 95-99 Eclipse at AUTOZONE,Advanced Auto, or Pep Boys and read up on this.