Coolant Change+Flush

Hey all, I have a 2000 5VZ 5-speed with oil cooler that will be getting a new timing belt, water pump, etc. soon. I'm stumped at the idea of flushing and burping the system. There seem to be a lot of contradicting opinions on this subject. Some say you need 2 gallons of Toyota red concentrate, some say 2.5 gallons. Some say to use a special funnel to help get the air out of the system. Do I flush it with distilled water or with the coolant? Some say the heater fan has to be on, others say it will just slow down the process by drawing heat away from the engine. And the pink coolant is supposedly backward compatible with these engines, from what I've read.


So there it is. What is supposed to be a simple task has turned into this. This will be my first coolant change I've ever done. Any help is greatly appreciated!!

 

If you want to simplify, switch to super long life. It’s compatible with the older vehicles and doesn’t need to be mixed.

when you drain the rad the only extra you need to do is remove the thermostat and heater lines to drain out the old.

2 jugs is super and you’d be good to go for a long time.

 

I'd suggest getting 3 gallons of Toyota (pink) Super Long Life Coolant. It's pre-mixed, not concentrated, so you just use it without any dilution.

I'd suggest getting a coolant flushing funnel, it will dramatically minimize the mess you make.

Here's the basic process:
1.) Park the truck ideally in a way that the truck sits slightly nose high. Drain the radiator petcock valve. Catch the old coolant in a drain pan or bucket and dispose of it. If you drain it with the radiator cap left on, it should pull most of the coolant out of the coolant reservoir too.

2.) Tighten the radiator petcock valve. Fill the radiator with distilled water using coolant flush funnel. Pour a small amount of additional water beyond what it takes to fill the radiator, as it should suck in more water as air bubbles burp from the system.

3.) Start the truck and turn the heater on max heat/max fan speed. Let the truck idle until bubbles stop escaping and the temperature gauge on the dash shows the engine is fully warmed up. Drain the radiator petcock valve.

4.) Repeat steps 2 & 3 as many times as necessary until the water being drained is very light pink or entirely clear.

5.) Tighten the petcock valve, fill the radiator with Toyota Super Long Life Coolant. Use the funnel to add a slight bit extra and once again start the motor, run the heater on max, until all bubbles stop burping and the temp gauge shows motor is fully warmed up. Top off coolant reservoir, to the max fill line ("F" mark). Replace the radiator cap.

Check the coolant reservoir when the motor is fully warmed up again the next day or later that week and top off with additional coolant if necessary (some additional air may burp and leave your cooling system slightly underfilled). Remember it should be at the full line on the reservoir when the engine is fully warmed up.

 

good advice^^^

when i took possession of my taco
the coolant was color of rusty water

took 5 flushes over 2 days to get water clear
-i just used hose water(didnt spurge on distilled water)
-bought one bottle of 'rad flush'.....i went back to store and got a 2nd bottle after 3rd flush. IIRC was a blue bottle forgot brand but recommended from members here

 

Other suggestions that may help:

* If you go to the dealership for coolant, they will sell you the correct blend for your truck. So no worries there. Likewise, the tech at the counter at the auto parts store should be savvy enough to know what you need. If you use a concentrate from an auto parts store, you *should* use distilled water when you dilute it to a 50/50 ratio. Distilled water will be free from trace minerals.

* I personally prefer to use the petcock (drain valve) on the radiator itself to drain the coolant. I make less of a mess that way. Others make very valid points to simply remove the lower radiator hose because it is a lot faster and also without the chance of you breaking that plastic valve.

* Either way, remove the cap to break vacuum, and drain it until it quits dripping. Then fill it until it is full. Drain and refill.

* There really isn't any "flushing" with this technique. Flushing is not needed unless you have a system filled with sludge. If that is the case, YouTube is your friend

* Don't worry too much about measurements. Drain it and refill it. Simple. As long as you replace what you get out and the volumes make sense, then so be it!

* Removing and replacing the thermostat is a very very good practice while you are at it. Pay attention to the orientation and take a picture when you remove it. It is a one-way flow valve and you do not wish to reinstall it backwards. Get the best one they sell at the auto parts store. If you really want to get your mad scientist thing going, then take that new thermostat and test it on your stove top in a small pot of water. Plop it right in there and turn on the gas. You cannot hurt it. It is supposed to operate like this. (No need for coolant though in the mac-n-cheese pot, water is just fine) It's kinda cool the first time you do it. As the water approaches boiling temp, you should easily be able to see the valve open. If you really want to be geeky, use a thermometer in the water. If it doesn't open fully by the time you have the first bubbles indicating a boil (212F), take it back and tell them you tested it and it didn't open. They will know exactly what you mean.

* This type of funnel can really help with removing the air pockets upon refill. That is a common issue. Harbor Freight or any auto parts store will sell them. Maybe even WalMart.

* Last but not least, and perhaps most importantly, if you are going to have your water pump and timing kit replaced at a shop, then just let them deal with it all. It will have to be replaced then anyway and there is no point in doing it twice. Same is true if you're going to tackle those jobs!
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* Whoops, one more tip. Once you get your timing belt and water pump and coolant replaced, then you will wish to make effort to fill the coolant (radiator) as full as you can. Whatever it takes. Proverbially speaking, you want to stuff 1.1 lbs of sausage into your 1 lb sausage link casing.

Just keep tilting over that coolant jug and letting the water pump pull it in. Using your fancy new funnel. I prefer to let the engine get up to a warm-hot state and then let it cool completely off and then do it again. Also, no matter what you do, be prepared for what I call "the last big burp behavior". This will usually occur during your gentle shake down drive. Bring extra coolant with you and a thick rag and gloves. Watch your temp gauge like a hawk. If it spikes up high, just simply ease off the gas and pull right over. Maybe wait a couple of minutes. Smoke one if you got one. Then pop the radiator cap off one more time and top it off. What happens is that last big air bubble will make its way to the top of the engine (because Sir Isaac Newton and his law of gravity says so) which is coincidentally where the engine coolant temp sensor is. That super hot air bubble is what can cause the temp to spike. This can cause obvious concern but can also be really easy to resolve.

And there you have it. HTH and best wishes!

 

Thanks and great advice. If there is any distilled water left in the system after flushing, won't that dilute the coolant?

 

Yes but it’s negligible. I used to use compressed air to get the last of it out

 

Don't you want to wait until the engine reaches operating temperature before you flip open the heater core valve to circulate, because it's going to take heat away and delay things? And what's the purpose of turning on the heater fan on an old mechanical system like this where you directly open the heater core valve with the cold-hot slider?

 

How much coolant should I buy?

 

A little over 2 gallons. Get 3, but you won't use much of the 3rd.

 

So from what I'm gathering:

3 gallons of Pink
-or-
2 gallons of Red + enough distilled water

 

Any brand of asian coolant will work. Valvoline Zerex, Prestone, Toyota SLLC, ect. You'll want 3 gallons total. If it's already pre mixed you don't need to add anymore distilled water. If it's not pre mixed then yes, 2 gallons and 2-3 gallons of distilled water.

My advice, buy the pre mixed. The mixture doesn't have to be a perfect 50 percent coolant and 50 percent distilled water, but close is good enough.

Flush the system, drain it, fill it, burp it, add a little more and be done. Don't over think it.