Bublling in the thermostat housing and very hot upper radiator hose

3.0L Engine

VIN S Engine

1. Before servicing the vehicle, refer to the precautions section.
2. Drain the cooling system.
3. Remove or disconnect the following:

• Splash shield
• Lower heater hose
• Radiator lower tube bolt
• Radiator upper front tube bolt
• Air cleaner assembly
• Battery and tray
• Water pump belt
• Upper radiator hose
• Engine vent hose
• Transaxle 10 pin connector
• Radiator bypass hose assembly
• Thermostat housing
• A/C compressor brace, if equipped
• Water pump mounting nuts
• Connector hose
• Water pump

To install:

1. Install or connect the following:

• Water pump
• Connector hose
• Water pump mounting nuts and tighten them to 15-22 ft. lbs. (20-30 Nm)
• A/C compressor brace, if equipped, and tighten the nuts to 15-22 ft. lbs. (20-30 Nm)
• Thermostat housing
• Radiator bypass hose assembly
• Transaxle 10 pin connector
• Engine vent hose
• Upper radiator hose
• Water pump belt
• Battery and tray
• Air cleaner assembly
• Radiator upper front tube bolt
• Radiator lower tube bolt
• Lower heater hose
• Splash shield

2. Fill the cooling system.
3. Start the engine and check for leaks.

Thermostat - 3.0L (2V) Removal and Installation

1. Partially drain the engine cooling system. For additional information, refer to COOLING SYSTEM DRAINING, FILLING AND BLEEDING .
2. Remove the three thermostat housing bolts. Fig. 25: Removing Thermostat Housing Bolts
   Courtesy of FORD MOTOR CO.
   
3. Remove the thermostat O-ring seal.
   • Inspect the sealing surfaces. Fig. 26: Removing Thermostat O-Ring Seal
     Courtesy of FORD MOTOR CO.
     
4. To install, reverse the removal procedure.

Thermostat - 3.0L (4V) Removal and Installation

1. Raise and support vehicle. For additional information, refer to JACKING & HOISTING .
2. Remove the front splash shield. For additional information, refer to FRONT END BODY PANELS .
3. Drain the cooling system. For additional information, refer to COOLING SYSTEM DRAINING, FILLING AND BLEEDING .
4. Remove the cooling tube bolt. Fig. 27: Removing Cooling Tube Bolt
   Courtesy of FORD MOTOR CO.
   
5. Lower the vehicle.
6. Remove the radiator upper cooling tube bolt. Fig. 28: Removing Radiator Upper Cooling Tube Bolt
   Courtesy of FORD MOTOR CO.
   
7. Disconnect the upper radiator hose and engine vent hose. Fig. 29: Disconnecting Upper Radiator Hose And Engine Vent Hose
   Courtesy of FORD MOTOR CO.
   
8. Remove the two bolts, and separate the radiator tube from the thermostat housing. Remove the thermostat. Fig. 30: Removing Bolts And Separating Radiator Tube From Thermostat Housing
   Courtesy of FORD MOTOR CO.
   
9. To install, reverse the removal procedure.

Follow the upper radiator hose off the radiator to the engine, where the house mounts on the engine is where the thermostat is located, two bolts should hold it on, front top side of the engine on the intake manifold.

1. 1 Drain the coolant from your Explorer into an adequate container by opening the drain plug at the bottom of the radiator. Save the coolant for reuse if it is relatively new and clean.
   
2. 2 Remove the negative battery cable from the battery if your Explorer has a 2.9-, 3.0-, 4.0- or 5.0-liter engine. This step is not necessary for 2.3- and 2.5-liter engines.
   
3. 3 Follow the upper radiator hose to the front driver's side of the intake manifold, where it meets the engine. This is where the thermostat housing on your Ford Explorer is located. If necessary, remove the air cleaner duct for easy access to the housing.
   
4. 4 Loosen the clip on the end of the radiator hose and pull the hose off the thermostat housing. Use a 10mm wrench or socket to remove the two retaining bolts on the thermostat housing cover. Remove the cover.
   
5. 5 Note the position of the thermostat before removal. Pull out the old thermostat. Seat the new thermostat inside the housing in the same position as the old one, spring-side facing into the engine. Install new gasket over the thermostat.
   
6. 6 Reattach the thermostat housing cover and the radiator hose. Reinstall the air cleaner duct if removed earlier. Fill the radiator with reserve or new coolant. Start your Explorer and run with the heater blowing until the engine gets warm. Check for leaks.
   

Read more: How to Change the Thermostat in a Ford Explorer ' eHow.com http://www.ehow.com/how_4484916_change-thermostat-ford-explorer.html#ixzz1CLSvmPwR

Place the drain pan under the drain valve on the radiator. Loosen the drain valve and allow the radiator fluid to drain. If the drain pan is clean, you can reuse the antifreeze.

Loosen the hose clamps on the upper radiator hose using a socket, screwdriver or pliers, depending on the type of hose clamp on the hose. Pull the hose off the radiator and thermostat housing. If the air filter intake hose is in the way, loosen the clamps and remove the intake hose (on some engines).

Unbolt the two bolts in the thermostat housings. Pry the thermostat housing off the engine block. Pull the thermostat out of the housing. Remove the old gasket and discard. Slide the new thermostat into the housing the same way the old one came out. Install the new O-ring seal in the housing. Coat the housing with a thin layer of silicone gasket maker. Allow the gasket maker to dry.

Slide the bolts into the thermostat housing, then line the bolts up to the bolt holes on the block. Slide the housing down the bolts until it touches the block. Turn the bolts in by hand to get them started. Tighten the bolts to 89 inch-pounds of torque.

Reinstall the upper radiator hose. Tighten the radiator drain plug. Fill the cooling system. Start the engine with the radiator cap off. Allow the engine to come up to operating temperature. Look for leaks. Watch the level of the water in the radiator. Fill as needed

Then replace the thermostat, because if on lower hose not hot and on upper hose scalding hot = antifreeze flow blocked by the thermostat wich remains closed!!!

Thermostat replacing:

You're going to lose some coolant, so have a bucket or other container, and some fresh coolant ready. Follow the upper radiator hose to the point where it's connected to the engine. The hose is clamped to a metal housing (water inlet) which is bolted to the engine. Remove the bolts (not the hose) and lift the housing to expose the thermostat (may require a little prying with a screwdriver or similar tool). Note how the old thermostat is fitted (which end is up), lift it out of the engine, and then remove all traces of gasket from the housing and the engine. Install the new thermostat and gasket, replace the bolts, add coolant as necessary, and you're done.

Before you start the job though, check the condition of your upper and lower radiator hoses. If they show any signs of wear, fraying, or fatigue, you might as well replace them too.

BillB

Explorer Thermostat LocationHere is advice for finding the thermostat:

• Follow the upper radiator hose from the radiator to the engine and there is a housing that houses the thermostat. Take it off and when you reinstall the thermostsat, make sure the spring goes toward the engine.

• The thermostat is located on the motor block under the three bolt flang that the top rediator hose connects to. Remove the three 10MM bolts and the thermostat can be removed for replacement.

How to Change an Explorer Thermostat

• 1. Remove the air cleaner air duct from the throttle body and air cleaner.
• 2. Follow the upper radiator hose to the engine to locate the thermostat housing. The housing is located at the front of the intake manifold.
• 3. Loosen the hose clamp, then detach the hose from the fitting. This can be difficult. If it's stuck, grasp with a pair of adjustable pliers and twist to break the seal. Then pull it off.
• 4. Remove the bolts and detach the housing cover. Be prepared some coolant may leak out as the gasket seal is broken. Remove the thermostat.
• 5. Install the new o-ring onto the thermostat (no gasket is needed) and install the thermostat into the intake manifold with the spring side pointing toward the engine.
• 6. Make sure the air release valve is in the up 12 o'clock position. Install housing cover and bolts. Reattach the hose fitting and tighten the hose clamp. Fill the cooling system with a 50/50 mix of coolant and water, and burp the system.

I would replace the thermostat. Sounds like it is stuck. Follow the upper radiator hose to where it hooks onto the engine. The thermostat is inside the housing that the hose hooks onto. Hope this helped and best wishes.

U should be able to locate it by following the upper radiator hose to the engine, where the hose is clamped to a housing . The thermostat is in the housing, which is usually secured w/ 2 bolts. If this doesn't help, let me know.