I opened my water pump housing on my 97 deville and the water pump looks fine and turns with key. i replaced a radiator and new thermostat just want some help before spending more money.

i would take a close look at the water pump
if the water isnt moving through the system it basically becomes a kettle
thats why steam comes out of the bleed nipple

Partially drain the radiator (drain is at the bottom on the driver's side of the radiator - you need to remove the front air deflector panel underneath the car to get at it). Remove the air cleaner assembly. Remove the outlet hose from the thermostat housing (this hose is the one attached to the top of the radiator on the driver's side - it is NOT the inlet hose which is routed across the top of the radiator). Remove the bolts holding the thermostat housing to the water pump, then the thermostat and gasket. Carefully clean off any gasket material from the water pump and housing, install the new thermostat and gasket, and reverse the procedure. Make absolutely sure you install the thermostat correctly - in must be installed in the same orientation as the old one.

2001 Cadillac Deville 4.6L SFI DOHC 8cyl Removal & Installation procedure...

1. Before servicing the vehicle, refer to the Precautions section.
2. Drain the coolant.
3. Remove or disconnect the following:
Negative battery cable
Upper fill panel, if equipped
AIR injection control valve, if equipped
Air cleaner
Oil level indicator tube nut, if necessary
Water pump belt cover
Water pump drive belt
Lower radiator hose
Thermostat bypass hose from the coolant inlet housing
Water pump cover

4. Remove the water pump by rotating it clockwise using special Tool J 38816-1A (water pump remover/installer).

To install:

1. Install the water pump with a new O-ring, by turning it counterclockwise using the special tool, until it stops. Torque the water pump to 73 ft. lbs. (100 Nm).

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Fig. To ensure proper operation, be sure to install a new O-ring (click for zoom)

2. Install or connect the following:
Water pump cover. Torque the bolts to 89 inch lbs. (10 Nm).
Lower radiator hose
Thermostat bypass hose to the coolant inlet housing
Water pump drive belt
Water pump belt cover
Oil level indicator tube nut, if necessary
Air cleaner
AIR injection control valve, if equipped
Upper fill panel, if equipped
Negative battery cable

3. Refill and bleed the cooling system.
4. Run the engine and check for leaks.


Hope this helps (remember to rate this comments)

The F-350 designation refers to a 1-ton Ford F-Series pickup truck. The thermostat in your diesel-powered Ford closes off the flow of coolant when the engine is cold, forcing the engine to heat up faster. When the coolant has reached a certain temperature, the thermostat opens up and the coolant flows as normal. A malfunctioning thermostat in your diesel may cause your engine to overheat if the thermostat gets stuck in the closed position. Installation of a new thermostat will cure the problem and get you back on the road

Open the hood. Allow the motor to cool off so that you will not be scalded by hot coolant. Locate the thermostat housing by tracing the upper radiator hose from the driver's side of the radiator to its termination at the thermostat housing.

2 Remove the cap from the white plastic coolant bottle at the front of the engine bay. Place a drain pan under the radiator drain petcock on the lower side of the radiator on the driver's side of the truck. Remove the petcock by rotating it counterclockwise with a 19mm wrench. Replace the petcock and tighten it in a clockwise direction once the coolant has fully drained.

3 Remove the clamps from both ends of the upper radiator hose with a pair of pliers. Pull the hose from the radiator and from the thermostat housing, using a twisting motion. Set the hose and clamps aside.

4 Spray penetrating fluid on the three mounting bolts on the thermostat housing and let it soak in for a few minutes. Remove the three bolts with an 8mm wrench turned counterclockwise. Remove the thermostat housing from the water pump and set it and the bolts aside.

5 Remove the thermostat housing from the water pump to reveal the thermostat. Carefully pry the thermostat up with a flat-blade

screwdriver if necessary. Clean the mating surfaces on the thermostat housing and at the water pump with a rag.

6 Place a new thermostat into the water pump with the pointed end facing upward. Install a new O-ring gasket into the groove on the thermostat housing mating surface of the water pump. Position the thermostat housing back onto the water pump and tighten the three bolts with a torque wrench to 15 foot-lbs.

7 Push the upper radiator hose back onto the radiator inlet and the thermostat housing until it is fully seated at both ends. Replace the hose clamps in their original position with a pair of pliers. Refill the coolant that you drained from the radiator back into the white plastic coolant tank and replace the cap. Start the engine and let it warm up. Check for leaks and retighten your connections if necessary

Two big hoses attach to your radiator. Look for the one that goes back to the TOP of the engine. There is a housing with two bolts in it that the hose connects to. Drain radiator, remove hose. Remove the two bolts. Remove the housing. Thermostat is inside housing or still on engine. It just pulls out. Remove any remaining thermostat housing gasket material from the housing and the engine. Install new thermostat. Should only fit in one way. Install new thermostat housing gasket and the housing. Reattach hose and fill radiator, leaving the cap off. Turn on the car and wait until car gets to warm condition. You will see the water start to move from the radiator to the engine when the new thermostat releases at the proper temperature. Replace the radiator cap and clean up, you are finished.

The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.
Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.
Take note of the orientation of the thermostat as you remove it.
Don't forget the new gasket, you may have to order this separately.

Assuming you have the Northstar engine....

The thermostat in the northstar engine is located at the bottom radiator hose (unlike most conventional cooling systems), the hose connects into the housing where you will also find the water pump.
Remove the hose from the housing,then remove the two bolts on the flange,the thermostat can then be pulled out.
Take note of the orientation of the thermostat as you remove it.
Don't forget the new gasket when you install your new stat.

i remember trying this. if your water pump is faulty. while the engine is off, spin the radiator blade. if it spins, then your pump is out, if it stops immediately, (it has a cluth of sorts) it's ok. also use a lower degree thermostat, like 160 degrees, then it will open sooner.

hello jaanutno, did you check to make certain the thermostat is operating? there may also be a weep hole on the water pump and you will see or feel some moisture there, you can remove the thermostat and boil it on the stove to see if it works once it reaches temp if it doesnt open you need a thermostat if it does work put the thermostat housing back together without the thermostst and start the vehicle to see if it will circulate one more thing to check is that the rad cap is proper for the radiator (how many psi) hope this gets you on the road good luck