90 Q45 coolant drain/refill

[gniknave]

I'm replacing my upper radiator hose either this evening or tomorrow and I've never done a coolant drain/refill before. What do I need to do?I did a search on this topic and found a couple of threads on it but none that really answered my questions. Bare with me, I'm smart about some areas of the car, dumb in others...I'm dumb in this one.

Is the radiator the only place I drain coolant from or is there somewhere else? Please be specific where.

I got some 50/50 Coolant/Water premixed. Is this ok to use or is something else (brand/mixture) recommended?

I may have more questions, but lets start there.

[redmanfx]

Theres a drain plug on the bottom of radiator. That the only place I know to drain the fluid besides the reserve resivoir.

Once drained, the real good way to make sure you get all the nasty stuff out is to fill with water, drive down the street and come back, drain again, repeat one more time. Then if your not in 35 to -20 degree temps fill with 70 percent "Distilled" water(not tap) and 30 percent Nissan Green antifreeze. If you are in freezing temps then go 50/50. I also use WaterWetter.

If you want to be slack then Drain the radiator(once) and fill 30/70 or 50/50 depending on the temp, using any antifreeze and no WaterWetter. Always use distilled water.

red

[DAEDALUS]

There are block plugs--left and right--on the bottom of the engine. Difficult to remove them, probably easiest done with the engine warm.

[gniknave]

Thanks!

How do I know how much, or when to stop filling the coolant? I hear it's til operating temp but I want to be sure.

[DAEDALUS]

Fill up the system, then use the fill line in the overflow bottle to get it just right. Usually there are 2 fill lines, one for hot coolant and one for cold coolant.

[JT_MONEY_2004]

I think the capacity if 10.4 qts, BUT, what i don't know is if this include what's around the block or just what get's drained/filled...maybe someone could confirm.

[elwesso]

You can only get out about a gallon out of the radiator (about 5qts)....

So 14 is what the entire system holds...

[gniknave]

From my experience (job done - thank you all by the way), what Wes said was pretty accurate.

[Q451990]

That's been my experience as well. My flushes usually start with running a chemical flush through... then about six gallons of distilled water (fill up, run until warm, drain, repeat) and then refilling with antifreeze. Those block drain plugs scare me since I've heard stories of them seeping...

Heath

[gniknave]

I didn't even bother to look for the block drain plugs after hearing the horror stories.

[911/Q45]

Girlie Men!

[elwesso]

you really are from Caul-e-fornia!!!

[JT_MONEY_2004]

while we're on the subject, what a good flush, only the bg stuff? Anyone know if prestone flush and fluid any good.

[elwesso]

I used this zerex stuff last time.. This spring im gonna get some stuff that you put in the radiator and force it out.....

IMHO if you do the coolant flush once really good and thorough, you can just do your once or twice yearly radiator drain/refil....

[nuQ]

so,,,when going with the 70/30 distilled water/coolant mix, the ratio should be based on 14 quarts not the 10.4 the FSM lists???????? very important i find this out quick!!!

[DAEDALUS]

Depends on what the FSM says. For my car it lists 10 7/8 qts. That's the entire system, excluding the reservoir tank.

[nuQ]

so what the FSM lists as the total quarts is what the ratio should be based on?

[elwesso]

No, if you only drain out a gallon, you need to use half and half, 60/40, whatever you have...

I have 60/40 mix already made ready to go, id suggest having like 4-5 gallons on hand...

[nuQ]

my procedure was to drain all from the radiator, fill with distilled, run the car for 5-10 minutes, drain again until the fluid is all clear (all distilled water). i then poured in coolent based on either the 30% summer mix or 40% winter mix ratio based on the total quarts which the FSM stated. is this correct????

[DAEDALUS]

That's how I do it, and Heath and Red too if I'm reading right. After flushing out the system, such that there's only pure H2O in there, drain what you can and then add enough pure coolant for a 30% mix of the total volume. Finally top off with pure H2O.

For 30% mix you should be adding close to a gallon of coolant before topping off, assuming total volume is a bit north of 10 qts.

[DAEDALUS]

You'll need a separate batch for the reservoir bottle if you're flushing that out too. Such a small amount, I wouldn't worry about it too much. If you put a simple 50/50 in there it won't do much to the total ratio.

[JedCoop]

I just replaced my water pump on my '92 Q.

l Got less than a gallon out of the radiator (completely removedf from the car)

After removing the Water Pump I had over two gallons of coolant (and some spillage).