How to Flush the Radiator in Cars

by Contributing Writer; Updated June 12, 2017

If you enjoy the feeling of the open road and going off road from time to time, then a Jeep car is the perfect vehicle to help you get away for awhile. It can take you places that most vehicles are prohibited from going. But along with your outdoor adventures, your vehicle is subjected to dust and debris that can clog up the cooling system and keep your engine from running its best. If you maintain a practice of flushing out your radiator at least once a year, you will ensure that your Jeep car keeps performing when you need to get away.

Under The Hood:

 How to Flush the Radiator in a Toyota Camry

Move the Toyota Camry to a flat area and set the parking brake. Then, open the hood, securely prop it up and touch the radiator. If the radiator is cool to the touch, proceed to the next step. If not, wait for it cool before you continue.

Twist the radiator cap one full turn, pause for a few seconds, and then completely remove the radiator cap. You want to pause because even though the radiator is cool, there can still be internal pressure. The one full twist of the radiator helps relieve that pressure.

Place a bucket with a minimum 2-gallon capacity, underneath the radiator and below the drain plug. The drain plug on a Toyota Camry is usually on the back passenger side of the radiator.

Open the drain plug and allow the coolant to drain completely from the radiator. You may need a socket wrench to loosen the drain plug. Once done, pour the old coolant into a sealable container for proper disposal later.

Close the drain plug and fill the radiator completely with distilled water. Then, open the drain plug to let the water flow into the bucket. The flushing requires about 3 gallons of distilled water. Repeat this process until there isn't any debris in the flush.

Make sure to close the drain plug again and refill the radiator with fresh coolant. In the Toyota Camry, you want to use Toyota Super Long Life Pink premixed coolant. Refill the radiator until it's within an inch of overflowing.

Start the engine and turn the heater to the high setting. Allow the Toyota Camry to run until the cooling fan turns on twice. Then, shut off the engine and check the coolant level. If it is lower, add more coolant. If not, screw the radiator cap securely back into position and close the hood.

Items you will need

  • Sealable container

  • Bucket

  • Coolant

  • Distilled water

 How to Flush the Radiator on a Jeep Liberty

Drain the engine coolant: Place a large container under the radiator drain fitting and open the fitting so the coolant will drain out. If the Liberty has a V6 engine, drain the remaining coolant from a second drain fitting at the engine block. Tighten the drain plugs afterward.

Unbolt and remove the thermostat housing from the engine using a wrench--tap the housing with a small rubber mallet if it is stuck. Remove the thermostat from the engine, then reconnect the thermostat housing without the thermostat.

Disconnect the upper radiator hose: Loosen its hose clamp with pliers. Insert a garden hose into the inlet the hose was connected to.

Turn on the hose and look for the water to come out of the disconnected radiator hose. Let the water run until it comes out completely clear, then turn off the water and remove the hose from the radiator inlet.

Reconnect the upper radiator hose using its clamp. Reinstall the thermostat, removing the housing so you can connect the thermostat to the engine, and then reinstall the housing with its bolts.

Fill the radiator with a fresh 50/50 mix of water and antifreeze--fill it slowly until the coolant reaches the base of the filler neck, then fill the reservoir to the "cold fill" mark. Run the engine with the radiator cap off. When the engine reaches operating temperature, the thermostat should open. Fill the radiator completely with 50/50 coolant solution.

Items you will need

  • Pliers

  • Wrench

  • Garden hose

  • Antifreeze

  • Rubber mallet

 How to Flush the Radiator of a Jeep Wrangler

Make sure the motor is cool before attempting to flush out the radiator. When safe to do so, remove the radiator cap from the radiator. Pour a bottle of radiator flush into the radiator and replace radiator cap. Turn engine on and follow instructions on back of radiator flush bottle. When finished, turn off vehicle and let it cool down. When safe, remove radiator cap.

Place a drain pan under the drain plug of radiator to catch coolant as it drains. The drain plug is located at the bottom of the radiator. Turn the drain plug by hand to drain coolant from radiator. If the plug is too tight, use a pair of pliers and gently turn plug. Be careful not to put too much torque on the plug or it will snap off.

Locate the heater hose for your Jeep Wrangler. The heater hose runs from the engine to the heater core through the firewall. Once the heater hose is located, find a section of hose that is free of obstructions and cut hose into two pieces with a utility knife.

Connect flushing tee from the radiator flush kit to the two sections of heater hose by placing a hose clamp on one end of the hoses and then inserting tee flange into the hose. Move hose clamp to the end of the hose so it can clamp the hose to the flange. Using a screwdriver, tighten the screw on the hose clamp. Repeat process for the other hose and flange. Make sure clamps are tight enough to prevent leakage.

Remove cap from flushing tee and connect back flow preventer to the tee. A back flow preventer is included in kit and has a black hose fitting on one end and a yellow fitting on the other. Screw the black hose fitting onto the flushing tee and connect the other end to a garden hose.

Locate the splash diverter (included in the flush kit) and attach it to the mouth of the radiator. Push down until you hear it snap into place. Connect old section of garden hose to the end of splash diverter and run the other end into a 5-gallon bucket to catch overflow of coolant.

Turn garden hose water supply on and allow it to run through engine and radiator until you see clear liquid running into the bucket. You may need to turn water supply off if the 5-gallon bucket is full and replace with another bucket, repeating the process until liquid runs clear.

Shut off water supply, then detach hose from flushing tee and replace tee cap. Remove splash diverter from radiator and refill radiator with coolant and clean water. Reattach radiator cap.

Items you will need

  • Bottle of radiator flush Drain pan Pliers Utility knife Radiator flush kit Screwdriver Garden hose attached to water supply Old section of garden hose 5-gallon bucket Antifreeze

 How to Flush a Radiator on a 2002 Cadillac Deville

Locate a level surface to perform the task, set the parking brake and brace the rear wheels using wheel chocks. Carefully raise the Cadillac and lower it onto the jack stands.

Put on your safety glasses, raise the hood and disconnect the battery to prevent from being accidentally shocked. Remove the radiator fill cap by hand to relieve the pressure from the cooling system.

Slide the fluid recycling container directly underneath the radiator drain plug, located on the bottom-left when facing the car. Reach up through the lower splash shield and loosen the drain plug to release the antifreeze (engine coolant) by turning it counterclockwise using a socket wrench. Drain half of the radiator coolant and move the recycling container aside.

Replace and tighten the radiator drain plug and pour in the complete bottle of radiator flush. Refill the radiator with water using your garden hose and replace the fill cap. Start the engine and allow it to idle for two minutes, then turn the engine off. Allow the engine to cool for several minutes before continuing onto the next step.

Put on gloves as an added precaution and place the empty bucket underneath the drain plug. Carefully remove the plug to release the water. Pour this flushed water into the recycling container and safely secure it closed.

Remove the fill cap and insert the water hose into the radiator fill opening, turn on the water and allow it flush for three minutes.

Turn off the water and re-plug the radiator drain. Reconnect the battery, safely re-jack and remove the jack stands.

Start the engine; allow it to idle while filling it with a 50/50 mixture of replacement antifreeze and water. Continue idling for several minutes with the radiator cap off to bleed out any trapped air in the cooling system. Replace the radiator cap by hand and check for leaks at the hose and drain connections.

Items you will need

  • 11 oz. radiator flush

  • Antifreeze coolant

  • Fluid recycling container

  • 5-gallon bucket

  • Garden hose

  • Floor jack

 How to Flush the Radiator in a 1998 Ford Expedition

Turn off the engine, and place the transmission in park if it's an automatic or first gear if it's a manual. Apply the emergency brake, and open the hood.

Place a rag over the radiator cap, and slowly unscrew it, allowing any excess vapor or pressure to escape. Remove the cap completely.

Crawl underneath the truck, and remove the hose clamp from the lower radiator hose using the flathead screwdriver. Place a bucket underneath the lower radiator hose outlet. Remove the lower radiator hose from the radiator and allow the coolant to drain out.

Remove the clamp from the upper radiator hose using the flathead screwdriver. Remove the upper radiator hose.

Place a garden hose inside the upper radiator hose inlet, and turn the water on. Allow the water to flow through the radiator and out the bottom at the lower radiator hose outlet. Continue pumping water through the radiator until nothing but clean water, free of dirt, debris and old coolant, flows from the lower radiator outlet.

Switch the hose to the radiator cap inlet, and flush water through the radiator again. Continue flushing until the water exiting the lower radiator outlet is clear. Reconnect the hoses, and refill the radiator with engine coolant. Replace the radiator cap, start the engine and check for leaks.

Items you will need

  • Clean shop rag

  • Flathead screwdriver

  • Plastic bucket

  • Garden hose connected to water supply

  • Engine coolant

About the Author

This article was written by the It Still Runs team, copy edited and fact checked through a multi-point auditing system, in efforts to ensure our readers only receive the best information. To submit your questions or ideas, or to simply learn more about It Still Runs, contact us.