Replaceing fan belt 1991 jeep renegade 4.0. no ac - how do yu add/remove tension?

It may depend on engine litre size. 4 cylinder shows top pulley for ac belt, needs to be loosened. to release tension.

6 cylinder shows tensioner pulley on mounting bracket for compressor. Loosen the bolt for tensioner pulley to release tension.

1991 4 cylinder with no AC

One of the idler pulleys has a built in spring loaded tensioner. You have to use a ratchet to turn it, which relieves tension on the belt while removing and also when replacing the belt.

there are 4 nuts or bolts its very easy

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.

You can do it. If it takes longer than 10 minutes something is wrong. If its a V8 make sure the tensioner is good, Fan belts rarely just "break" so check all the pulleys.

There is an idler pulley close to the power steering. Loosen the bolt that goes through the front of the idler pulley first. Then you will see the head of a bolt looking up at you. Turn the bolt clockwise to tighten and counterclockwise to loosen. The pulley is attached to the threaded bolt and it moves the pulley up or down as needed to adjust the belt tension. When the belt is replaced turn the bolt until the belt is tight. Remember to check the belt again after a few hundred miles. A new belt will stretch and loosen.

For the 1991 DODGE DYNASTY - V6 3.3L 201ci GAS FI N R , review this informacion:

Belt Routing Diagram
- Multiple Accessory, w/o A.C. (Mfg. After 2/27/91)
- Multiple Accessory, w/A.C. (Mfg. After 2/27/91)
- Multiple Accessory, w/o A.C. (Mfg. Before 2/27/91)
- Multiple Accessory, w/A.C. (Mfg. Before 2/27/91)



Remove the serpentine belt by using a breakover bar, rachet or serpentine belt removal tool with the correct size socket for the pulley mounting bolt. Rotate tensioner arm to release tension. Remove the belt.

Hope helped with this (remember rated this help) Good luck.

May be a weak tensioner that needs replacing. Make sure you clean pulleys well with brake cleaner or similar as well. I have had one with similar problem, that Gator back belt was causing it. I'm not 100% convinced that a notched belt will get as good a grip as a complete rib all the way around the belt. Just doesn't add up to me. If you compare that to tire grip, then you'd be telling me that snow tires would work better on the Nascar circuit?

the only reason for the belt coming off the pulley is the something in the belt path is off aligment.
put the belt back on and chek the path where the belt pass. water pump, alternator, AC compressor, Power steeling unit, etc....... or even the pulley tensioner itself.
chance are there is a belt in the wrong pully slot.