How to Install a Thermostat & Air Bleed a Chrysler 3.3by Justin Cupler
The Chrysler 3.3-liter engine is cooled by a mixture of antifreeze and water. The flow of this mixture is regulated by the thermostat. When the engine requires cooling, the thermostat opens and allows the cooled mixture into the engine, while the hot mixture is transferred to the radiator for cooling. Over time, this thermostat can stop functioning properly and the engine will overheat. The only way to rectify the problem is to replace the thermostat, then bleed the cooling system.
Open the vehicle's hood and locate the upper radiator hose, the rubber hose that connects to the top of the radiator. Place the drain pan directly below the upper radiator hose.
Trace the upper radiator hose toward the engine until you reach the metal connection point between it and the engine, this is called the thermostat housing. Loosen the hose clamp holding the upper radiator hose to the thermostat housing, using a ratchet and socket, and pull the hose from the housing. Be prepared for a small rush of coolant to come from the hose and fall to the drain pan.
Loose and remove the two bolts holding the thermostat gasket to the engine. Pull the housing from the engine, exposing the thermostat.
Pull the thermostat and gasket from the engine. Scrape the remnants the old thermostat gasket from the thermostat housing and the engine, using a razor blade scraper.
Place the new thermostat into the engine with the spring part going into the engine.
Place the new thermostat gasket around the engine, lining up the holes in the gasket with the holes in the engine.
Place the thermostat housing on the engine and tighten the bolts to 21 foot-pounds, using a torque wrench and socket.
Push the upper radiator hose back onto the thermostat housing and tighten the hose clamp, using a ratchet and socket.
Raise the front of the vehicle with the floor jack and secure by placing jack stands beneath it. Lower the vehicle until its weight is only on the jack stands.
Open the Chrysler's radiator cap and start the vehicle. Add 50/50 premixed coolant until the radiator is full.
Allow the vehicle to run and add coolant each time the level drops. The drop in coolant level is the thermostat opening, allowing coolant into the engine. Stop adding coolant when the radiators coolant level stays consistent.
Observe for any bubbles forming in the coolant in the radiator, this is a sign of air in the system. The Chrysler 3.3-liter has an automatic bleeder in the thermostat, known as a jiggle-valve. Allow the vehicle to remain running with the front end lifted until no bubbles appear, this bleeds the air.
Place the cap on the radiator and shut down the engine. Raise the Chrysler off of the jack stand, using the floor jack, and pull the jack stands from under the vehicle. Lower the vehicle to the ground.
Close the Chrysler's hood.
- Never work on the Chrysler while the engine is hot, always allow it to cool first.