How to Install a Radiator in a Lexus SC 400by Eli LaurensUpdated July 06, 2023
The Lexus SC 400 is manufactured with a pressurized coolant system that uses a finned radiator to stabilize the engine temperature. This radiator can become corroded or damaged, requiring replacement. The average backyard mechanic can replace the radiator in a Lexus in about an hour.
Things You'll Need:
- Socket set
- Drain pan
1. Disconnect the battery
Disconnect the battery by turning the positive terminal bolt in a counterclockwise direction, then setting it aside. Do not let it touch metal.
2. Drain the radiator
Drain the radiator by turning the radiator petcock counterclockwise and allowing the coolant to fall into the drain pan. The petcock is on the lower corner of the radiator; it's a white or black plastic bolt. Uncap the radiator to relieve the negative pressure.
3. Remove the upper and lower coolant hoses
Remove the upper and lower coolant hoses by pinching the hose clamps and working them off the radiator nipples; in some cases the clamps are screw-type and must have their clamp screws turned counterclockwise to come off. The hoses can be worked off the nipples, but leave them connected to the engine.
4. Remove the fan and fan shroud
Remove the fan and fan shroud by turning the corner bolts in a counterclockwise direction, then unplugging the wiring harness adapter by pulling it apart. The fan and fan shroud will pull straight up and out of the engine compartment.
5. Remove the top radiator mount plate
Remove the top radiator mount plate by turning the mount bolts in a counterclockwise direction, then pulling the mount plate free.
6. Remove the radiator by pulling it toward the top of the engine compartment
Remove the radiator by pulling it toward the top of the engine compartment and working it out of the mount rails. Set the radiator aside.
7. Replace the radiator with a new unit
Replace the radiator with a new unit by sliding it into the mount rails and into position, then reattaching the mount plate and securing it with the bolts by turning them clockwise.
8. Reconnect the fan and fan shroud
Reconnect the fan and fan shroud by turning the corner bolts clockwise, then reattaching the wiring harness connector by pressing the ends together until you hear a click.
9. Reconnect the coolant hoses
Reconnect the coolant hoses by working them onto the radiator nipples, then securing their hose clamps by pinching them together or turning their screws clockwise until snug.
10. Tighten the radiator petcock
Tighten the radiator petcock, if applicable, and refill the system with coolant.
11. Reconnect the battery
Reconnect the battery by turning the positive terminal bolt clockwise until snug.
12. Crank the motor and continue to pour coolant into the radiator
Crank the motor and continue to pour coolant into the radiator until it can take in no more. Cap the radiator, and check the level of coolant in the reservoir tank often.
Tips and Warnings
Use a mixture of 50 percent water to 50 percent antifreeze for average conditions. Use distilled water for added protection.
Be careful not to leave coolant where animals or children can get to it; it is a poison.
Video showing how to replace a radiator on a car:
Comments on this video:
- Thanks Scotty! When I want to know the basic steps quickly with all of the needed information you are the man. Three minutes! Other videos are at least twenty minutes are lectures or life stories!
- Thanks Scotty! I didn't have a good way to take off the clapms - the "take them off at the engine trick" worked great for most of the hoses, except the one from the bottom to the engine - it was the toughest for me. The only other thing I had to deal with not on the video were tiny plastic clips holding electrical wiring - I learned that you just have to squeeze them out/through. All in all a successful install, which I attempted because of your video. Sincerely, Jen
Eli Laurens is a ninth-grade physics teacher as well as a computer programmer and writer. He studied electrical engineering and architecture at Southern Polytechnic University in Marietta, Ga., and now lives in Colorado.