Where do you drain the coolant so I can change my thermostat gasket?

Drain coolant, undo bolts at housing slowly and evenly, they are located at the end of the upper rad hose.Pull off housing, and pull out thermostat. Replace and do opposite to install. Top up with 50/50 coolant mixture. Make sure you clean gasket area and install new gasket. Do not over torque bolts...

drain coolant until its below the thermostat.then remove two thermostat housing bolts.remove thermostat housing and thermostat.make note position of thermostat before removing it.then carefully clean all old gasket material from thermostat housing and cylinder block you can buy can gasket remover at any auto parts stores.buy new thermostat gasket.if you have the paper type you need to buy RTV SILICONE to help seal gasket if you have rubber type gasket you dont need RTV SILICONE.make sure both surfaces are clean.then install new thermostat and new gasket.if you have paper type gasket apply thin 1/16 coat RTV SILICONE both sides thermostat gasket.then install gasket to thermostat housing then install housing to cylinder block first make sure new thermostat in place before installing thermostat housing. let RTV silicone sit up about hour before adding coolant.IF THERMOSTAT HAS THE O RING SEAL DONT NEED RTV SILICONE AND THE PAPER GASKET.

DRAIN COOLANT LEVEL DOWN BELOW THERMOSTAT.PLACE DRAIN PAN UNDER VECHICLE TO CATCH ANTIFREEZE.WHEN DONE PUT ANTIFREEZE SAFE PLACE FROM KIDS AND ANIMALS.WHEN DONE DRAINING SOME ANTIFREEZE.FOLLOW RADIATOR HOSE TO TOP OF INTAKE TO THERMOSTAT HOUSING. LOOSEN HOSE CLAMP REMOVE RADIATOR HOSE FROM THERMOSTAT HOUSING.THEN LOOSEN HOUSING BOLTS.REMOVE THERMOSTAT HOUSING AND THERMOSTAT.CLEAN BOTH THE THERMOSTAT HOUSING SURFACE AND INTAKE SURFACE YOU CAN USE ACETATE OR BRAKE CLEANER AND SCOTCH BRITES ROLL OF CLEAN PAPER TOWEL. AFTER CLEANING HOUSING AND INTAKE SURFACE MAKE SURFACE CLEAN SMOOTH FROM THE DEBRIS WHEN DONE. TAKE THERMOSTAT PUT GASKET SEALER ON BOTH SIDES OF GASKET PUT GASKET TO THERMOSTAT HOUSING MAKE SURE GASKET AND THERMOSTAT HOUSING HOLES ALIGN CORRECTLY.NOW PLACE NEW THERMOSTAT IN PLACE IN THE INTAKE.MAKE SURE THERMOSTAT SPRING END GOES TOWARD ENGINE FACING DOWN.THEN INSTALL THERMOSTAT HOUSING WITH GASKET TO THE INTAKE.TORQUE THERMOSTAT HOUSING BOLTS TO 20 FT LBS.WAIT 1 HOUR BEFORE POURING ANTIFREEZE BACK IN THE COOLANT SYSTEM GIVE THERMOSTAT GASKET SEALER LITTLE TIME TO CURE.SO YOU WONT HAVE COOLANT LEAKS.NOW IF THERMOSTAT HAS THE LARGE O- RING ON IT YOU DONT HAVE A THERMOSTAT HOUSING GASKET THE THERMOSTAT O- RING IS THE SEAL THAT HOLDS COOLANT INSTEAD OF GASKET.WHEN THERMOSTAT AND HOUSING IN PLACE.INSTALL RADIATOR HOSE TO THERMOSTAT HOUSING TIGHTEN HOSE CLAMP.THEN FILL RADIATOR BACK UP WITH THE COOLANT YOU DRAIN OUT.START VECHICLE UP. THEN CHECK FOR LEAKS.

JUST DRAIN COOLANT LEVEL BELOW THE THERMOSTAT. CATCH COOLANT IN A DRAIN PAN UNDER RADIATOR.THEN REMOVE RADIATOR HOSE FROM THERMOSTAT HOUSING ON THE CYLINDER BLOCK.THEN REMOVE THERMOSTAT HOUSING AND THERMOSTAT.CLEAN THERMOSTAT HOUSING SURFACE AND THERMOSTAT HOUSING SEALING SURFACE ON CYLINDER HEAD.INSTALL NEW THERMOSTAT IN PLACE,MAKE SURE THERMOSTAT AIR BLEED HOLE FACING LEFT SIDE UPWARD ON THE ENGINE.SOME THERMOSTAT HAS TOP STAMPED ON IT.MEANING MUST BE FACING UP.WHEN THERMOSTAT IN PLACE.TAKE NEW THERMOSTAT GASKET.PUT SEALER ON BOTH SIDES OF GASKET.THEN.PUT GASKET ON THERMOSTAT HOUSING.THEN PUT HOUSING IN PLACE TORQUE HOUSING BOLTS 16 - 20 FT LBS.WAIT 1 HOUR UNTIL GASKET SEALER CURE.THEN FILL UP COOLANT SYSTEM.BLEED COOLANT SYSTEM AND CHECK FOR LEAKS.

Detach coolant hose after draining down the coolant below that level. Take off the housing, you may need a rubber mallet to break seal/gasket. You might as well replace thermostat while your there. Use new gaskets or sealant, then put on new housing nice and tight. Reattach coolant hose and refill radiator. The coolant temperature sensor is near there and if old you should change this also while you are doing this and coolant level is already lowered.

AutoZone.com lists the following procedure for several engines. If your engine is different, try going back to autozone.com with exact engine spec.


Removal & Installation

1.5L, 1.6L, 1.8L & 2.0L Engines

1. Drain the coolant to a level below the thermostat.
2. Remove the water inlet fitting, gasket and thermostat.
3. Clean the gasket mating surfaces.
   
   Fig. Exploded view of the thermostat-1.5L engine shown, 1.8L similar
   
   
   Fig. Exploded view of the thermostat-1.6L engine
   
   
   Fig. Water inlet fitting (A) and thermostat-2.0L engine
   

To install:

1. Place the thermostat in the housing with the jiggle valve facing upward. Install a new thermostat gasket.
   
   Fig. Use a new gasket (A) when installing the thermostat (B)-2.0L engine shown
   
2. Install the water inlet fitting and tighten to 14-19 ft. lbs. (19-26 Nm) for 1.5L, 1.6L and 1.8L engines, or to 11-15 ft. lbs. (15-20 Nm) for 2.0L engines.
3. Fill the engine with coolant, then start the engine and check for leaks.

2.4L & 2.7L Engines

1. Drain the coolant to a level below the thermostat.
2. Remove the engine coolant outlet fitting and gasket.
3. Remove the thermostat.
4. Clean the gasket mating surfaces.
   
   Fig. Thermostat mounting-2.4L engine
   

To install:

1. Install the thermostat. Make sure that the flange of the thermostat is correctly seated in the socket of the thermostat housing. If the thermostat is installed in the wrong direction, the bottom of the thermostat will touch the rib inside the intake manifold, making it impossible to seat flange in position
2. Install a new gasket and the engine coolant outlet fitting. Tighten the fitting bolt to 7-11 ft. lbs. (10-15 Nm) for 2.4L engines or to 12-14 ft. lbs. (17-20 Nm) for 2.7L engines.
3. Fill the engine with coolant, then start the engine and check for leaks.

Drain some coolant from radiator to below level of thermostat housing. Be careful to keep pets away as coolant is very sweet smelling and poison. Remove two bolts holding thermostat housing in place and use catch pan to catch fluid. Clean all gasket material from both sides of housing. Clean threads of bolts and use gasket shellac on them and new gasket. Install thermostat same as old one was, install new gasket, tighten bolts to correct torque value as found in your handy dandy shop manual. Refill radiator and check for leaks.

Follow the large hose coming out of the top of the radiator. That should take you to the thermostat housing. You need to place a container under the drain spigot on the radiator and drain a gallon or so of coolant from the radiator so that coolant doesn't run out when you remove the housing. Remove the housing (usually don't need to remove hose) and scrap clean both surfaces of the housing and the block. Take not of the position of the gasket and thermostat you are removing. Replace thermostat, put a small amount of gasket sealing material on both surfaces, put new gasket on and tighten the housing back down. Some engines have a small plug in the housing. You have to remove the plug as you replace coolant back into the motor until you see coolant running out of the hole and then put the plug back in.

Here is a video that show the gist of changing one.
http://www.youtube.com/watch?v=RIC6Z4D6Q3E

FIRST OF ALL YOU HAVE TO DRAIN SOME COOLANT.JUST ENOUGH SO COOLANT WONT FLOW ALL OVER ENGINE.AND COOLANT TO EXPENSIVE ON THE GROUND.TO GET TO THERMOSTAT.YOU HAVE TO DISCONNECT CONNECTORS TO MAF EGR IDLE SPEED CONTROL AND IAT SENSOR.. REMOVE THROTTLE AND SHIFT CABLES FROM BRACKET.REMOVE AIR FILTER ASSEMBLY WITH MASS AIR FLOW SENSOR.REMOVE BOTTOM PORTION OF AIR FILTER HOUSING.REMOVE COOLANT HOSES FROM THROTTLE BODY.THEN REMOVE THROTTLE BODY ASSEMBLY.YOU HAVE TO DISCONNECT SMALL COOLANT HOSE TOP WATER PUMP.REMOVE SMALL BOLT THAT HOLDS METAL COOLANT LINE TO WATER PUMP.THIS LINE HAS TO BE MOVE JUST ENOUGH SO YOU CAN REMOVE THROTTLE BODY.ONCE THROTTLE BODY OUT THE WAY YOU CAN REMOVE THERMOSTAT.BESURE WHEN YOU PUT EVERYTHING BACK TOGETHER.REPLACE THROTTLE GASKET AND THE COOLANT HOSES COME OFF THROTTLE BODY BESURE TO USE OLD COOLANT HOSES MEASUREMENTS FOR NEW HOSES MEASUREMENTS MAKE SURE YOU BUY THE CURVE HOSE FOR THROTTLE BODY. DONT TRY TO USE STRAIGHT HOSE IT WILL KINK AND CAUSE NO COOLANT FLOW.WHEN YOU ARE DONE.FILL COOLANT BACK TO CORRECT LEVEL AND BLEED COOLANT SYSTEM.

make sure engine is cool then drain coolant by opening the drain plug at bottom of radiator. remove cap from radiator so coolant will continue to drain and when coolant is down enough to pull off upper radiator hose at intake then close drain, then remove two bolts at coolant housing and remove thermostate. clean gasket material from intake and housing and replace with new gasket and thermostate tighten bolts install hose fill rad with coolant water mix 50/50 and run engine with heat on floor until gets hot and you see coolant flowing in rad, install cap