How to Locate and Replace a Thermostat on a 1992 Dodge Grand Caravan ES

Chrysler Corporation was the first company to market the minivan.

The Dodge Grand Caravan Long-Wheelbase was introduced in 1987 as a longer version of the Dodge Caravan. The 1992 Dodge Grand Caravan SE was a two-wheel-drive minivan. The 1992 Grand Caravan was available in a four-wheel-drive version. The 1992 Grand Caravan SE was equipped with a 3.3-liter V-6, capable of producing 150-horsepower. The thermostat in the 1992 Grand Caravan SE controls the flow of coolant through the engine, by opening and closing. When the thermostat goes bad, it is either stuck open, or stuck shut, and will need to be replaced.

Things You'll Need

• Vehicle ramps
• 1-ton or greater capacity floor jack (if ramps are not available)
• 2 jack stands (if ramps are not available)
• 3/8-inch drive ratchet and socket set
• Razor blade or box cutter blade
• New thermostat
• New water box gasket
• 1 1/4-gallons 50/50 premix coolant (green or universal)
• 3/8-inch drive torque wrench (reading inch pounds)

Instructions

1. Raise the front of the minivan, using vehicle ramps. If vehicle ramps are not available, use a jack to raise the front end of the vehicle. Place jack stands underneath the front sub-frame, on either side of the engine. Lower the vehicle onto the jack stands.

2. Lay beneath the front bumper and slide your body into position to access the back of the radiator. Slide a drain pan beneath the radiator, and set the opening about one foot behind the radiator. Loosen the lower radiator hose clamp with a ratchet and socket, or a pair of pliers if it is a squeezable clamp. Move the clamp back toward the engine about six inches. Remove the radiator hose from the radiator and let the fluid drain into the pan for no less than three minutes.

3. Install the radiator hose back onto the radiator and slide the clamp back into position on the hose. Tighten the radiator hose clamp with a ratchet and socket until it is snug. Move the clamp with pliers, if it is a squeezable clamp.

4. Open the hood of the Grand Caravan, and set the hood prop. Visually inspect and locate the thermostat housing on the passenger side of the engine, near the top. The thermostat housing has single coolant hose running into it, and the housing is attached to the water box. The thermostat housing resembles a football with two bolts at the narrow ends. The entire assembly is located directly next to the ignition distributor assembly.

5. Remove the two thermostat housing bolts with a ratchet and socket. Pull the thermostat housing and heater hose away from the water box, exposing the gasket and thermostat. Remove the thermostat with a pair of pliers, then place it directly into your drain pan. Remove the gasket with pliers and place it in the drain pan, as well.

6. Clean the water box gasket mounting surface with a razor blade or box cutter blade. Make sweeping motions with the blade, away from the large hole in the center of the water box. Be sure to remove all of the old gasket material from the water box, then double-check and remove any gasket material stuck to the thermostat housing outer lip.

7. Install the new thermostat into the center of the water box mounting hole. Make sure the side of the thermostat with the spring is facing inward, into the water box. Install the new thermostat gasket onto the water box. Install the thermostat housing onto the water box, and tighten the bolts to 180 inch-pounds, using a 3/8-inch drive torque wrench and socket.

8. Remove the radiator cap, and add 3/4-gallon of 50/50 premix coolant into the radiator. Allow the coolant to sit for about a minute before adding additional coolant. Add coolant a second time to top off the radiator.

9. Start the engine with the radiator cap off the radiator. Turn the heater control panel dials to defrost, full heat and full fan speed. Allow the minivan to run for about 15 minutes. Add coolant to the radiator, as the level of the coolant drops. You will see air bubbles exiting the radiator. This is called "bleeding" the cooling system. Continue adding coolant, until you have added 1 1/4-gallons of coolant to the cooling system. Shut the engine off when the air bubbles stop coming out of the radiator cap hole. This process can take as long as 1/2-hour.

10. Replace the radiator cap, making sure you turn it twice. Push down and turn the cap clockwise until it won't turn any farther. This will lock the cap into its final safe position.

11. Empty the drain pan into an empty coolant bottle. Take the used coolant to a local auto shop or oil change shop. Most of these facilities will gladly dispose of your used coolant for free. Do not dispose of coolant in a drain or sewer, as this will cause the coolant to enter your ground water system.

Tips & Warnings

• Automotive coolant or antifreeze contains Ethylene Glycol, which is an extremely toxic substance. Wash your skin for 15 minutes with warm water and soap if you contact the coolant at all. Ethylene Glycol is poisonous to both humans and animals. Make sure you do not leave coolant spills on the ground. Saturate the spill with liquid cleaner or dish soap, then spray the area for approximately five minutes.

• If you feel dizzy at all during this project, stop and seek medical attention immediately, as you may be suffering from Ethylene Glycol poisoning. Ethylene Glycol can enter your bloodstream through your skin, your eyes, your mouth, and your lungs. Do not induce vomiting if you feel you have ingested Ethylene Glycol.

References

• Cars Direct: 1992 Dodge Caravan SE Specifications
• AutoZone: 1992 Dodge Grand Caravan 3.3L, Thermostat Replacement Instructions