I have a couple questions that don't seem to have been answered on my searches.

1. What is the total capacity of coolant?

2. How much water is still left in the block is you just drain it out, without draining the block? I need to know to compensate adding in 100% Toyota Red coolant later.

 

dang... you are thinking way too much about this.

 

There wouldnt be water left in the block anyway, you would be left with a mixture...

 

What vehicle are we discussing ... LX470 or GS400 ?

Under the "Engine Specifications" section of your owners manual has the total capacity for your cooling system.

The only way to know how much coolant is left in the block after draining the radiator is to measure the amount drained.

The purpose of draining the coolant is to exchange all of it, since it deteriorates over time. Draining the block with a couple of pieces of 5/16 clear plastic tubing is reasonably simple.

 

We are talking about the GS400. I'm not thinking "too far" into this as I'm exchanging fluids. Currently I don't think it has Toyota Red in there. I don't want to be mixing the Red with whatever brand is in there.

I want to keep flushing the system with ordinary tap water until all of the old coolant is gone. Then taking into account whatever amount of pure tap water is left in the block, after *numerous* flushing, I will add appropriate Toyota Red + more water in there.

 

I would not put tap water into the cooling system...

Especially the oyster shell enriched water of New Jersey. The water minerals tend to clog the radiator and heater core, once introduced.

It is a newer practice to use bottled distilled water to flush the system. Then drain and refill with the distilled bottled water. The water is commonly available in most grocery stores.

If the replacement coolant is premixed, it is recommended to use the coolant itself to flush the system, but personally, I feel this is a little extreme. The idea is not to introduce any contaminates into the cooling system. These are not the brass based radiators of yesterday; but aluminum and plastic, and is more susceptible to corrosion.

 

Yea, us Supra guys use disstilled water too. But when I flush a radiator, esp when changing brands of fluids, I use tap water because I flush it *a lot* of times. Then in the final stages, I will then introduce disstilled water to save money.

And at around $18 a gallon, I wouldn't use Toyota Red to flush it.

 

Here is a simple way to do this if it has only been a year or so since you have drained it. Drain the old fluid from the radiator and the puke tank. Fill the system with tap water. Run the engine a few minutes to circulate everything. Drain again. Refill with a 50/50 Toyota Red and distilled water. If you fill up with tap water, no matter how often you drain, you can still get some electrolisys (sp?). Some people this bothers, some it don't. Your call!. Mix up the 50/50 in some jugs before you start. Don't just dump in a gallon of Red then top off with water. Your cooling capacity will go down bigtime. Toyotas/Lexus in general over build their cooling system as long as they are well maintained. Most aren't. I drain mine every 30K on my GS300 and my Explorer. Plan to do the same with my Vette. I don't ever add tap water. The problem comes in when the system has not been maintained, like not changing the fluids until 100K or the car has overheated before. By using the 30K rule you change out about 85% of the fluids before they breakdown so you don't worry about getting them all out. And yes I have tested my pH and it is a about 10.5 which is what you want!

 

flush it with distilled. what is it, 79 cents a gallon?

 

I agree, if it were my car I would use distilled, but since I maintain the system, no need to flush!

 

can anyone confirm to purge the air out of the system, turn up the heater and top off coolant once the theromostat kicks in.

 

This is correct, purge the coolant with the heater at MAX or FULL.

Fill the overflow reservoir about an inch above the MIN mark with coolant mix and replace the tubed plastic cap.

With the radiator cap removed and engine running, top it off as the thermostat opens and the level falls in the radiator tank. It's a good idea to wrap a rag around the radiator filler neck to catch any spill or overflow.

Cap it off, bring the engine to normal operating temperature and allow to purge itself by way of the coolant reservoir.

After allowing the engine to cool, monitor the level in the radiator tank by removing the cap to insure the coolant tank is full. Check the overflow tank has not dropped below the MIN mark.

Let the system stabilize a couple of days; then top off the overflow reservoir to full when the engine has fully warmed up.

It is normal for the coolant level to rise and fall as much as a couple of inches in the reservoir between cold and hot operating temperatures.

 

Have you considered waterless coolant ?

 

Sighs, lol. I'm not trying to start a "how to properly flush coolant thread". I just simply need some numbers.

1. coolant capacity

2. how much is left in the block if you simply drain the plug

 

Apologize for the tangents ...

9.5 quarts

If you're draining the radiator plug only, about 2/3's the capacity, I would suspect.