Someone has complained here that there is no coolant change DIY. Having just done one so here it is.
This is for a 4-cylinder 5S-FE, someone do the same for a V6.
Capacity: 6.8L with heater
Tools and supplies
Container with measures or litre scales
1 jug of Toyota Long Life Coolant. Although the '97 still specified the regular stuff, Big Pig being 14 years old means this may allow me to not worry about changing coolants anymore. '99 specified Toyota Red, so settle for nothing less.
4 jugs of distilled water. A dollar a jug at your local grocery store.
Garden hose with spray nozzle
10mm wrench, 10mm socket, ratchet
Big enough pliers for the hose clamp.
Old jugs for old coolant disposal (optional)
Oil filter wrench
Probably all the required supplies for an oil change
0. WAIT UNTIL THE CAR COMPLETELY COOLS DOWN.
1. Drain the coolant. The radiator drain plug is to the driver side. Reach down and feel for it. Slide a drain pan under it. Open radiator cap and drain plug.
2. If you have no extra jugs around, pour one jug of distilled water into the bucket to vacate one to store old coolant for disposal.
3. Remove coolant overflow tank bolt and pull tank straight up. Pinch the clamp on both sides of the overflow tank hose and disconnect that as well. Dump the old coolant inside. Clean it well inside and out. The garden hose nozzle comes in handy. Rinse with some distilled water you stashed away for this job. Set aside.
4. Using a pair of pliers, loosen the clamps at both ends of both radiator hoses. You will really have to reach down for the radiator end clamp of the lower hose.
5. Disconnect upper radiator hose from radiator end. Immediately plug it with your palm, and don't let go until you can point it downwards into the drain pan. Don't worry if some coolant spills on the subframe. It's no big deal. Once all coolant has been dumped, disconnect the other end and free the hose.
6. Slide the drain pan underneath the general area of the lower radiator hose. Disconnect the lower radiator hose. Coolant will come gushing out. This is why you need that drain pan in position first.
7. Remove lower radiator hose. You will need to wiggle and pull hard.
8. With both hoses out, look inside them. Using the garden hose, clean out as much scale deposits as you can. I didn't find much deposits inside the lower hose, but the upper one... ugh, not even a pressure washer can rid it of them all.
9. Remove two 10mm nuts and the water inlet. The upper one is on a union stud which came out for me with the nut. This stud is M6x1 on both ends so just jam two nuts on the other end and wrench it off, if this happens to you. The lower one is a bitch to get to because the A/C compressor is in the way. I have no 1/4" flex socket and nothing else can fit in there. This is my only access method:
Stubby or flex wrench may save you from having to do this but I have none, and the oil filter gets in the way of my regular 10mm wrench. The only way I can undo that nut is to remove the oil filter, albeit temporarily. I eventually went on to do an oil change as that is overdue too.
WARNING: Before you run water through the cooling system, put the old oil filter back on hand-tight. Remove oil filter only for thermostat housing nut access. You do NOT want water in your engine oil!
10. Thermostat may come out together with the water inlet because of the gasket. Note that there is a notch on the housing and a loose piece - the jiggle valve - on the thermostat. They need to line up to within 5 degrees when you put them back together. With the notch at 12 o'clock, the jiggle valve also needs to be at 12 o'clock. Got it? Now wrap a clean towel around it and pull it off. With both separated, wipe everything down clean inside and out - inlet, thermostat, gasket. If you have money to spare, buy a new gasket beforehand. But don't put these together just yet; you need the thermostat out for the flush.
Take this chance to pour all drained coolant in the pan into a jug. Mark it for proper disposal.
The part you all have been waiting for: Flushing the cooling system
11. Reinstall water inlet without the thermostat. Temporarily plug the lower end of radiator hose into the water inlet. Also reinstall the upper radiator hose. Don't worry about the clamps until you are ready for final coolant fill. You should have it like in the next picture, except it shows the upper rad hose disconnected from radiator. That's fine - you'll need it like this during the second flush.
If you can, take the chance to turn the car's temperature control to full hot, just in case. I didn't do it but it doesn't seem to matter.
12. Lower radiator outlet will be open. Slide a drain pan underneath again. Close radiator drain plug and put radiator cap back on. You are about to do the first of two flushes.
13. Jam the garden hose with spray nozzle into the S-shaped lower rad hose, now very high up and easily accessible. Now see why you have to install it this way?
Now let the water run until the drain pan is almost full. This first drain will show the old coolant's color.
Not quite there yet...
This stuff should be less noxious than the first drain. If you have extra jugs, store these for disposal too, otherwise just dump them down your toilet. NOT THE STORM DRAIN! You want these to go through your city's sewer treatment.
Subsequent flushes should show less and less color. Repeat until the water coming out is clear.
14. This is the second of two flushes. Pull garden hose out. Disconnect the upper rad hose from radiator. Jam garden hose into this. Place the bucket under the lower rad hose. *If you had poured distilled water into this bucket, pour them into a CLEAN jug. You will rinse the cooling system with these later. Plug garden hose into upper rad hose. Let water run. Pause for emptying the bucket if you have to, but keep going until water from this flush is also clear.
15. Flush the radiator. Pull the lower rad hose and plug it into the top radiator port. Point the hose up. Plug garden hose in and let water run. Keep going until water coming out is clear. Alternatively, block the upper port with your hand, point garden hose at where radiator cap goes and spray into it.
Distilled water rinse
16. From your stash of distilled water, save one new jug for the final coolant fill. This jug will constitute your final 50/50 mix. Any water coming out of the cooling system from this point on is clean and can be left on the ground if you feel like it, or better yet, catch them for reuse.
17. Install the lower radiator hose the correct way. This will plug the lower radiator port so it can be properly rinsed. Now open the radiator drain plug and radiator cap.
18. Using a funnel, run 1-2 jugs of distilled water through the upper radiator hose.
19. Place funnel on radiator. Close drain plug. Fill radiator with one jug of distilled water. Drain. Repeat until the one jug is completely through.
20. Now you are done with the flushing. It's time to put things back together. Remove both upper and lower radiator hoses and put the clamps back on. Remove the water inlet and install the thermostat and gasket to it. Remember how they have to line up? Thermostat spring points away from water inlet while jiggle valve needs to line up to within 5 degrees of that water inlet notch. While holding the thermostat to the housing to keep alignment correct, install the water inlet. Torque, if you can get a torque wrench in there, is 78 inch-pounds. Install the upper and lower radiator hoses. The bend on the upper hose should stay away from the auto transmission dipstick.
21. Reinstall overflow tank, connect the overflow tank hose.
Final coolant fill
22. Make sure drain plug is closed. Knowing that only distilled water is left in the cooling system and it holds 6.8 litres, measure half of that - 3.4 litres - of Toyota Red and pour into radiator using a funnel. If the radiator becomes full. squeeze the upper rad hose to let it burp. Check for leaks. This stuff is expensive! After all 3.4 litres of Toyota Red has gone in, top off with distilled water slowly, squeezing the hoses as needed, until the radiator is finally full and no more burping is possible.
23. Measure how much Toyota Red is left and make a 50/50 mixture with distilled water. Pour the mixture into the overflow tank to the full line. Save any extras for future. After a few runs tank level will go down as the cooling system continues to work air out on its own.
24. Run the engine. Again check for leaks.
Congratulations, you have completed your very own coolant flush and change and won't have to worry about it again for the next 5 years.