Celica GTS 2000-2006 Coolant replacement procedure
Celica GTS radiator flush, Coolant drain, air burping
Materials: 1 Gallon Toyota red Long life Coolant, 2 gallons distilled water
Tools: Bright spot light, Fiber video camera, 10 mm socket wrench, vice grip, pliers, trash bag, coolant pan, rubber gloves
This is a critical procedure, doable but far more critical and difficult than the oil change. If you bungle it, the engine may overheat and crack. Toyota recommends this procedure every 50K miles and performed by authorized dealer.
You should do it step by step carefully while checking for leaks. After doing it a few times you will understand how the cooling system works, and can spot any problems.
Unlike older cars, the Celica has a closed radiator similar to BMW and MBZ. Coolant must fill the engine block first then flow over to the radiator via the upper 2-inch hose. Engine when hot will open the thermostat to send about half a quart of coolant from the radiator into engine block for cooling, while burping air from the top of radiator out to the reservoir. This half quart of coolant needs to be added back to the reservoir before air bleeding.
If you want to do it yourself, there is a label under the hood, with instructions and a sketch of the coolant reservoir and hoses to help you do it, but the instructions lack details. Follow it to the T to be safe, or you may risk overheating the engine.
There are 4 main simple steps: draining, refilling, blowing air out and burping:
A. Drain the coolant out of the radiator and engine block, then close all hoses and valves
B. From the reservoir feed about 1 gallon coolant into engine block and radiator.
C. Idle engine until it turns on fan and pumps coolant from radiator into block and blows air out from radiator to reservoir. Let the fan cycle on /off a few times to blow out air.
D. Close reservoir, rev to 3K RPM every 5 seconds to burp the smaller air pockets.
Below is a detailed step by step procedure.
1. Replace coolant when engine is cold or you may get burns. Need up to about 2.3 gallons of total coolant and distilled water mix. Best to use Toyota red Long Life Coolant diluted in half with distilled water.
2. Park the car on a level spot. Put xmission in PARK, set hand BRAKE, HEATER ON HIGH, chock the rear wheels carefully.
3. Remove the plastic engine bay cover on passenger side to expose the white grapefruit-sized coolant reservoir on top of the radiator.
4. Before doing any work, CHECK LEAKS using SPOT LIGHT and FIBER CAMERA. Look for red traces on floor, bottom cover, hoses and clamps, radiator's bottom edges, air burping nipple on radiator's top driver side under the air box. If any red residue, find out where it leaks from and fix it. Squeeze and check all hoses and connections for leaks, cracks. This is the easiest and cheapest time to fix potentially big, expensive problems on the road.
5. On top of the reservoir, open the 2 clamps and remove the 2 quarter-inch rubber hoses. Be gentle, dont pull the air bleed hose as it's connected to a plastic nipple on the radiator's top, which can break.
6. Remove the 10 mm bolt on top of the reservoir, raise it about 6 inches and insert it on the hood's hook using the slot on its bottom. The reservoir's bottom should now be slightly higher than the top of the head, a few inches higher than the engine block and the radiator's top to feed coolant into all of them. Remove the reservoir cap and the white plastic butterfly air bleed valve on the reservoir.
7. Place an open trash bag under the radiator outlet on passenger side to catch coolant. Position a pan under the car to collect any spills.
8. I WOULD AVOID Toyota's 2 recommended drains; the butterfly valve at the radiator's bottom on driver side, and the engine block drain under exhaust manifold. These 2 drains are very difficult to access.
Instead the 2-inch exit hose at the radiator's bottom, on passenger side, is easier to access and open. Clean around hose and radiator bottom. Use a vice grip or a pair of pliers, hold open the clamp and pull this hose out to drain coolant out of the radiator's bottom into the trash bag.
9. When coolant stops draining, clean the hose and area on radiator, reassemble the 2-inch hose back to the radiator. Remove the coolant-filled trash bag or pinch a hole on it and let it drain into the pan under the engine bay.
If elect to open and replace the thermostat, use 10 mm socket with universal joint to open 2 nut plates behind the alternator. You dotn need to remove the radiator and the belt, which is a lot of work. Wiggle the dome cap out and remove the thermostat. Only about half quart will drain out out of here. When put back, thermostat must be flat with the bleed hole on top.
10. There is another 8 mm drain bolt under the engine block, in front of the exhaust manifold, to drain engine block, but the car would have to be raised about 12 inches on solid stands. If you drain the engine block, the system will need to be refilled with total 2.3 gallons of coolant, including about half a quart in the heater core.
11. I would skip the flushing with chemicals since it's too complicated, time consuming and can leave residues in the cooling system. If needed, flushing should be left to a dealer. Optionally you may want to do steps 12,13 and 14 below to flush with just distilled water. Close the system up, fill the cooling system with distilled water, run the engine to normal operating temperature to turn on fan and water pump to circulate the water into the block and radiator, turn off the engine, dump the water out for extra cleaning without air burping, before refilling with new coolant and air burping.
There should be about 1 gallon of distilled water remaining in the system so you could add undiluted coolant to achieve 50% dilution.
12. After closing up all hoses, with reservoir's cap and air bleed valve open, start adding about 3.7 liters or 3.5 quarts of coolant (about 7/8 of a gallon) into the reservoir up to its FULL line. Coolant should flow through the bottom hose into the engine block, taking about 10 to 15 minutes. Let coolant flow in and keep adding as level in the reservoir goes down.
Coolant will fill engine block first, then flow through the upper 2-inch hose into the radiator. When radiator is full, coolant will seep out of the air bleed hose. Use the spot light and fiber camera, insert it into crevices and inspect carefully the floor, top and bottom of radiator, under the air box and around all coolant hoses for clues of leaks. If there are leaks, stop, check for causes carefully and repair/replace any faulty parts before continuing. Any leaks are much easier and cheaper to fix now than loss of coolant at high speed which may burn the engine.
System is full when the coolant starts dripping out of the 1/4 inch AIR BLEED HOSE on top of the radiator, next to the reservoir, and/or when coolant level in the reservoir stops going down. Stop adding coolant to reservoir.
13. Lower and assemble the reservoir in its place. Reassemble the two 1/4 inch hoses (2 hoses) on the right of reservoir and secure their clamps. Check for leaks on all hoses, connections, bottom of engine bay and the floor.
14. With A/C OFF, HEATER OFF, start and IDLE engine until COOLING FAN starts BLOWING, then wait for FAN to STOP. Let fan cycle on /off a few times. Hot air and some coolant should be blowing out of the AIR BLEED hose into the reservoir. Most of the air is blown out of radiator in this step. It takes about 15 to 20 minutes for fan to start. You can speed it up by closing the hood to keep engine hot.
When engine gets hot to normal operating temperature (mid range on indicator), it will open the thermostat and pump about half quart of coolant from the radiator into the engine block for cooling. Watch the ENGINE TEMPERATURE indicator at all time. If OVERHEAT shut down immediately and troubleshoot. Wait about 5 minute for engine to cool down before restarting.
If the system was filled properly, the fan should cycle on and off every few minutes to cool and pump coolant into engine block. After 10 to 15 minutes the air bleed hole should spray out some coolant and burp out some hot air. This means the burping is near completion as most of the air on top of the radiator has been blown out, and the radiator is blowing some coolant out with the hot air. Turn on and check the HEATER, if it's not blowing hot air then coolant is not circulating into heater, or leaks cause coolant to drain off heater or engine block. Trouble shoot and find the leaks.
15. Add coolant to FULL level in reservoir. The cooling system is supposed to be full with about 2.3 gallon of coolant max, depending how much you drained from the engine block, including what's in the reservoir. If not then there is a leak or overfilling. Do not leave reservoir empty as the engine will suck in air and requires more burping.
16. Close reservoir's CAP and BLEED VALVE. Turn heater off to stress the cooling system, rev the engine INTERMITTENTLY to 3000 RPM FOR 5 sec then IDLE for 5 sec ( for about 15 - 30 minutes ) to burp the rest of the small air pockets out of radiator into the closed reservoir. Watch the engine temp gauge. If temperature gets high or near the red zone, turn off engine to let large hot air bubbles go past the temp sensor, then restart in about 1 minute.
The remaining air bubbles will go pass the temp sensor in the system to burp out and will sometimes cause overheat spike. If temp goes back to normal within 1 to 2 minutes, then the air bubbles are small. If it still overheat after 5 minutes then the hot air bubble is very large, or coolant may have leaked out of engine, leaving it dry, or the cooling system may have other problems. This step should burp out most of the air, but there may be still some small bubbles which will be burped out into the reservoir as you drive.
17. Wait for engine to cool down, check coolant level. Check ONLY WHEN ENGINE IS COOL. Coolant level should be between LOW and FULL or something may be leaking, or there are AIR BUBBLES still in cooling system. Check and fix any leaks under engine, under the air box and on all coolant hoses. Add coolant to FULL level if low.
Drive the car in the next few days with a gallon of coolant / distilled water while monitoring and ADDING COOLANT if LOW. If ENGINE TEMPERATURE goes into HIGH LEVEL turn off engine and restart in 5 minutes.
Reassemble the top engine cover.
Note 1: A quick spike of high temp into the red zone is likely a large hot air bubble moving past the temp sensor. To be safe turn off engine and wait 1 minutes. When restart temp should come back down to normal after 1 minute.
Note 2: If you still have overheating problem, depending on severity, you can drive the car without stressing the engine and watch engine temp, coolant levels and check for leaks on the floor, radiator and coolant hoses.
If engine temp stays higher than mid range, the coolant line may be blocked somewhere. Engines filled with hard tap water usually have calcium deposits that will calcify and restrict or block the flow. You may trouble shoot and perhaps drain the coolant out again and try to clear the blockages with just distilled water and calcium dissolving chemicals. If still overheat perhaps call a tow truck and head for the dealer.
I have done this procedure 5 or 6 times without problems. It's simple and straight forward. Engine will get up to normal temp fairly quickly and coolant level is always as expected.
Note 3: The butterfly drain valve at bottom of radiator, driver side, drains coolant out of the bottom via a 1/4 inch hose. There are 2 ways to access this valve to but both are very difficult.
From the bottom you have to stick your fingers into the U channel, which the radiator sits in, and try to push open or close the butterfly valve. Perhaps a slotted tool that fits over the butterfly would make it easier to turn.
From the top you would have to take out the air box with lots of vacuum hoses and connectors, in a very tight space. It may take a few hours for removing and reassembling, risking damaging or forgetting hoses, wires.
Note 4: The air bleed hose is hooked into the radiator's plastic top via a molded-in 1/4 inch plastic nipple (black ABS) that may be easily broken or weakened, especially on old radiators. Try not to pull the hose or knock on the nipple too hard. Check for leaks from this nipple under the air box.
If broken, there are various repair nipples in eBay (mostly for BMW and MBZ). I bought a plastic nipple from Ace Hardware, enlarged the hole on radiator slightly with a drill bit for a snug fit, hammered the nipple in and seal the joint generously with 2-part epoxy. Cured epoxy is supposed to be stronger than ABS plastic. Try to flush out any plastic debris from radiator.
Brass nipples with threads are also available but brass expands less than ABS plastic and may cause leaks in time.
If this nipple leaks again, it may be prudent just to put in a new radiator. After market Aluminum-top radiators sell in eBay for about $100 to $200. Toyota's plastic-top radiator sells for $400 retail. Koyorad supposedly supplies OEM radiator to Toyota. You can buy a Koyorad's all aluminum rad on eBay for about $150.