I have removed all the water pipes from the thermostat housing and a long bolt but the ousing seems difficult to coe loose for my Jaguar 2.2 Diesel?

1) Drain the cooling system

2) Remove the bolts that secure the thermostat housing to the water pump feed pipe.

3) Remove the feed pipe.

4) Remove the thermostat and retaining sleeve, noting the orientation for installation.

To Install:

1) Install the thermostat and retaining sleeve with the dimple placed into the housing slot.

2) Install the feed pipe that connects the thermostat housing to the water pump.

3) Install the bolt that secures the water pump feed pipe, and tighten the bolt to 18 inch lbs.(10 Nm).

4) Fill the cooling system.

2.2L Engine To Remove:

1. Drain the cooling system.
2. Remove the exhaust manifold heat shield.
3. Remove or disconnect the following:
4. Thermostat housing to water pump feed pipe
   
5. Remove the thermostat cover bolts from the thermostat housing.
6. Remove and discard the thermostat housing O-ring.
7. Thermostat assembly
   
8. Twist the water feed pipe while pulling to remove it from the water pump. Remove the water pipe from the water pump assembly.
9. Remove and discard the seals from the water pipe.
10. Remove the inner thermostat sleeve.
11. Remove the thermostat assembly.

To Install:

1. Install the thermostat cartridge into the thermostat housing while aligning the cartridge tangs up with the thermostat housing bolt holes. This will assure the inner sleeve can be completely installed.
2. Align and insert the inner sleeve notch into the thermostat housing. If the inner sleeve notch is not properly positioned, the sleeve will not completely seat into the housing.
3. The water feed pipe seals can be slightly lubricated with silicone gel to aid during installation. Install a new O-ring on the water pipe.
4. Position the water pipe into the water pump assembly.
5. Seat the water feed O-ring by pushing and twisting toward the water pump. Take care not to tear or damage the O-ring.
6. Install the thermostat housing cover to the water pipe. The water feed pipe has a locating tab to assure proper alignment.
7. Install a new thermostat housing cover seal into the recess groove.
8. Position the thermostat housing cover into position.
9. Install the thermostat housing cover bolts and tighten bolts to (89 in-lb 10 Nm).
10. Install the exhaust manifold heat shield.
11. Fill the cooling system.

1. Diconnect negative battery cable.

2. If the vehicle has an automate transaxle, remove the exhaust manifold before proceeding with the removal and installation of the thermostat.
3. Drain the cooling system. 4. Take out the bolts that hold the water pump feed pipe to the thermostat housing. 5. Lift out the thermostat-housing-to-water-pump feed pipe. 6. Pull out the thermostat. 7. Set the new thermostat in position. 8. Connect the thermostat housing-to-water-pump feed pipe.
9. Set the bolts in place that holds the thermostat-housing-to-water-pump feed pipe. Torque the bolts to 89 inch pounds. 10. Install the exhaust manifold. 11. Refill the cooling system to the proper level with a 50 / 50 mixture of distilled water / DEX Cool approved coolant. 12. Start the engine and check for leaks. 13. Make the necessary adjustments to coolant levels to assure optimum engine performance.

Please see my tip at http://www.fixya.com/cars/r5929960-s_thermostat . These are generic instructions. Specific instructions from autozone.com for your car are pasted below. If you get stuck, please get back to me.

1. If equipped with an automatic transmission, remove the exhaust manifold.
2. Drain the cooling system.
3. Remove the thermostat housing to water pump feed pipe bolts.

Remove the thermostat housing to water pump feed pipe.

Fig. Remove the thermostat

Remove the thermostat.

To install:

1. Install the thermostat.

Install the thermostat housing to water pump feed pipe.

Fig. Install the thermostat housing to water pump feed pipe

1. Install the thermostat housing to water pump feed pipe bolt and tighten the thermostat housing to water pump feed pipe bolt to 89 lb inches (10 Nm).
2. If equipped with an automatic transmission, install the exhaust manifold.
3. Fill the cooling system.

The short answer is yes you can do this repair with little repair experience. Locate the upper radiator hose and follow it back to the block, assuming you have already gone and picked up the new thermostat and a seal and form-a-gasket. Once you locate this point on the engine where the upper radiator hose connects to the block you need to remove the radiator hose from the engine. After removing the hose, get the proper sized socket to remove the 2 to 3 retaining bolts that hold this mount to the engine and remove it. Under that piece you will find the thermostat. Take it out, paying attention to the direction the old thermostat is installed, clean off the old seal and sealing compound. Place the new thermostat in place then apply a thin bead of Form-A-Gasket to the cover piece and carefully lay the seal in place on that, make sure you line up the mounting holes. Place a bead of Form-A-Gasket on the motor side and then replace the thermostat cover and radiator hose mount. Once you have it tightened down securely re-attach the hose and fill the radiator. Test driver the vehicle after letting everything sit for about 30 minutes if you find a leak tighten the bolts near the leak to seal it up and the job is finished. Should take about an hour with drying time and test driving.

Thermostat Removal & Installation 2.2L Engine To Remove:

1. Remove the exhaust manifold. If equipped with an automatic transmission.
2. Drain the cooling system.
3. Remove or disconnect the following:
   
   
   • Thermostat housing to water pump feed pipe bolts.
     
     
   • Thermostat housing to water pump feed pipe.
   • Thermostat.

To Install:

1. Install or connect the following:
   • Thermostat.
   • Thermostat housing to water pump feed pipe.
   • Thermostat housing to water pump feed pipe bolt.
     1. Tighten bolt to 89 in lbs (10 Nm).
   • Exhaust manifold if equipped with an automatic transmission.
2. Fill the cooling system.

2.4L Engine To Remove:
Thermostat assembly 2.4L

1. Drain the cooling system.
2. Remove the exhaust manifold heat shield.
3. Remove the coolant inlet housing mounting bolts through the exhaust manifold.
4. Raise and safely support the vehicle.
5. Remove the coolant inlet housing stud from the oil pan.
6. Remove wheel and tire assembly.
7. Remove the engine splash shield.
8. Remove the mounting bolts from the transaxle-to-engine block support. Remove the support.
9. Remove the coolant housing pipe.
10. Remove the thermostat.
11. Clean the mating surfaces.

To Install:

1. Install the thermostat.
2. Install the coolant housing pipe.
3. Install and secure the transaxle support-to-engine block mounting bolts.
4. Install the engine splash shield.
5. Install the wheel and tire assembly.
6. Install the coolant inlet housing stud to the oil pan.
   • Tighten to 19 ft lb (26 Nm).
7. Lower the vehicle.
8. Install the coolant inlet housing bolts through the exhaust manifold.
   • Tighten the coolant inlet housing bolts to 10 ft lb (14 Nm).
9. Install the exhaust manifold heat shield.
10. Fill the cooling system.
11. Inspect the system for leaks.

3.4L Engine To Remove:

1. Drain the cooling system.
2. Remove the air cleaner.
3. Remove exhaust crossover pipe.
4. Disconnect the surge tank line fitting from the coolant outlet.
5. Remove the thermostat housing to intake manifold bolts.
6. Remove the thermostat housing outlet and thermostat.

To Install:

1. Install the thermostat and housing outlet.
2. Install the thermostat housing bolts.
   • Tighten the thermostat housing bolts to 18 ft lb (25 Nm).
3. Install exhaust crossover pipe.
4. Connect the surge tank line fitting to the coolant outlet.
   • Tighten the fittings to 15 ft lb (21 Nm).
5. Install the air cleaner.
6. Fill the cooling system.
7. Inspect the system for leaks

Removal & Installation 2.2L VIN 4 To Remove:

1. Drain the cooling system.
2. Remove the lower radiator hose from thermostat housing.
3. Remove the thermostat housing bolts and outlet.
4. Remove the thermostat.
5. Clean the mating surfaces.

To Install:

1. Install the thermostat.
2. Install the thermostat housing and bolts.
3. Install the coolant housing bolts. Tighten bolts to 14 Nm (10 ft. lbs.).
4. Install the lower radiator hose to thermostat housing.
5. Fill the cooling system.
6. Inspect for leaks.

2.2L VIN F To Remove:

1. Remove the exhaust manifold. If equipped with an automatic transmission.
2. Drain the cooling system.
3. Remove or disconnect the following:
   
   
   • Thermostat housing to water pump feed pipe bolts.
     
     
   • Thermostat housing to water pump feed pipe.
   • Thermostat.

To Install:

1. Install or connect the following:
   • Thermostat.
   • Thermostat housing to water pump feed pipe.
   • Thermostat housing to water pump feed pipe bolt. Tighten bolt to 10 Nm (18 in. lbs.).
   • Exhaust manifold. If equipped with an automatic transmission.
2. Fill the cooling system.

2.4L VIN T To Remove:

1. Drain the cooling system.
2. Remove the exhaust manifold heat shield bolts and shield.
   
   
   
   
3. Remove the coolant inlet housing bolts.
4. Lift vehicle.
5. Remove the coolant inlet housing stud from the oil pan.
6. Remove the wheel.
7. Remove the right engine splash shield.
8. Remove the transaxle-to-engine block brace bolts and brace.
9. Remove the radiator outlet pipe.
10. Remove the thermostat.
11. Clean the mating surfaces.

To Install:

1. Clean the mating surfaces.
2. Install the thermostat.
3. Install the radiator outlet pipe.
4. Install the transaxle-to-engine block brace and install bolts.
5. Install the right engine splash shield.
6. Install the wheel.
7. Lower the vehicle.
8. Install the exhaust manifold heat shield and bolt.
9. Tighten the exhaust manifold heat shield bolts to 14 Nm (10 ft. lbs.).
10. Fill the cooling system.
11. Inspect the system for leaks.

Alero, Grand Am 1999-2005 Thermostat - Removal & Installation 2.2L Engine

1. If equipped with an automatic transaxle, remove the exhaust manifold, as outlined in this section.
2. Drain the cooling system.
3. Remove the thermostat housing to water pump feed pipe bolts.
4. Remove the thermostat housing to water pump feed pipe.
   
   
   Fig. Thermostat mounting-2.2L engine
   
5. Remove the thermostat.

To install:

1. Install the thermostat.
2. Install the thermostat housing to water pump feed pipe.
3. Install the thermostat housing to water pump feed pipe bolt. Tighten the thermostat housing to water pump feed pipe bolt to 89 inch lbs. (10 Nm).
4. If equipped with an automatic transaxle, install the exhaust manifold, as outlined in this section.
5. Fill the cooling system.

3.1L Engines

1. Disconnect the negative battery cable.
2. Drain the cooling system to a level below the thermostat housing.
3. Remove the air cleaner assembly.
4. Disconnect the surge tank line from the thermostat housing.
5. Remove thermostat housing-to-intake manifold attaching bolt and nut, then remove the housing.
6. Remove the thermostat.

To install:

1. Clean all gasket surfaces completely.
2. Insert the thermostat in the intake manifold.
3. Attach the thermostat housing to the intake manifold.
4. Install the mounting bolt and nut. Tighten to 18 ft. lbs. (25 Nm).
5. Install the air cleaner assembly.
6. Connect the surge tank line to thermostat housing.
7. Refill the cooling system.
8. Connect the negative battery cable, remove the radiator cap, then start the engine. Allow the engine to run with radiator cap removed, until the upper radiator hose becomes hot (thermostat open). With the engine idling, add coolant to the radiator until the level is up to the bottom of the filler neck.
9. Install the radiator cap, making sure the arrows line up with the overflow tube.

3.4L Engine

1. Drain the cooling system.
2. Remove the air cleaner.
3. Remove exhaust crossover pipe.
4. Disconnect the surge tank line fitting from the coolant outlet.
5. Remove the thermostat housing to intake manifold bolts.
6. Remove the thermostat housing outlet and thermostat
7. Clean the mating surfaces.

To install:

1. Install the thermostat and housing outlet.
2. Install the thermostat housing bolts. Tighten the thermostat housing bolts to 18 ft. lbs. (25 Nm).
3. Install exhaust crossover pipe.
4. Connect the surge tank line fitting to the coolant outlet. Tighten the fittings to 15 ft. lbs. (21 Nm).
5. Install the air cleaner.
6. Fill the cooling system.
7. Inspect the system for leaks.

Hope this help (remember comment and rated this).

You will need a 1/2" socket with ratchet, and a 1/2" wrench for the actual removal of the thermostat housing. First, remove the air duct from the air filter housing and the air intake connection to the engine. Set aside. Next, remove the upper radiator hose from where it connects to the engine by loosening the hose clamp. At the other end of this part where the hose was removed from is the "L" shape that houses the thermostat and bolts to the engine. This part (housing) has two bolts. The top bolt will require the use of an extension on your ratchet which you will need to insert between the water bypass pipe and the exhaust heat shield before coupling with the 1/2" socket. Loosen the top bolt. The bottom bolt will require the use of the 1/2" wrench, as the socket will not fit due to the location of the heat shield. NOTE: the bottom bolt only needs to be LOOSENED and not removed, as the housing has an open "C" at the lower bolt location allowing the housing to pivot upward from that bolt. After removing the top bolt and loosening the lower bolt, you can pivot the "pipe" end of the housing downward and carefully maneuver the housing out of its location. You should now see the thermostat. Clean surfaces of the engine and housing well. Insert the new thermostat with the "spring" into the engine and the "bell" outward. Be sure the seal is seated properly into its socket in the engine. Position the housing carefully, making sure not to move the thermostat out of position. Reassembly is the reverse of removal. In my case, I did not use any gasket seal. The thermostat has a rubber seal on it which works well on its own. Adding gasket seal may make removing the housing in the future more difficult

The thermostat is in a difficult position. Follow the upper radiator hose and it leads into the block under the throttle body. 
Remove the air filter assembly and you'll c what is the exhaust manifold crossover pipe right in front of the thermostat housing.
 NICE, it gives you very little room to remove the 2 bolts to the housing and once u remove those then you'll find you have the thermostat housing loose but because of that darn exhaust manifold crossover pipe u don't have enough room to take the thermostat housing out to change the stinking thermostat. 
So from what you can see, you have to remove the heat shield which is cased around the exhaust manifold crossover pipe and if you still can't get enough room to remove the thermostat, (which you amy find out)then you'll have to remove the crossover pipe as well just to change the thermostat. 
If you have to remove the crossover pipe then their are 2 bolts on both ends of the pipe leading into the manifolds. But then the tough parts done and once u switch the thermostat over and ATTENTION:remove any old gasket material and put a new gasket in it's place then installation is reverse of removal. 
Good luck and hope this helps,