Does antifreeze color matter if I do a system flush?

[zxcvbob]

My 2010 Ford Focus is due for a coolant change.  I don't think I've ever changed it in this vehicle so was going to flush it first.  Drain, fill with distilled water, run with the heater on until the thermostat opens. Repeat.  Drain it again, add a little over 3 quarts of concentrated antifreeze (system capacity is 6.7 quarts), then top up with distilled water.  Mix up a little 50/50 for the overflow tank.

Prestone Universal okay? Is my procedure okay?  I'll check it after a few days with one of those floating-ball hydrometers to make sure I got the mix close enough.

[Boomhauer]

If you intend to use that  then flush it out completely and thoroughly and you’ll be fine. Do two or three water changes and you should be ok. Prestone makes a cheap flush kit to tie into a heater hose and hook up a garden hose to it for better flushing action too.

Coolant color, or rather the makeup of coolants definitely matter. Mixing wrong coolant formulations *expletive deleted*s *expletive deleted*it up.

[Bogie]

If you mix the old "green" stuff with Dexcool, you get something akin to tapioca.
 
I'd stick with the "universal" coolants. They are not "optimal," but they probably won't cause problems, and unless you are the original owner, you have no idea what someone may have added.

[Lennyjoe]

Dexcool is for Cheby’s correct?

[zxcvbob]

If you mix the old "green" stuff with Dexcool, you get something akin to tapioca.
 
I'd stick with the "universal" coolants. They are not "optimal," but they probably won't cause problems, and unless you are the original owner, you have no idea what someone may have added.

I am the original owner.  If I have had the coolant changed before it was at the dealer, but I don't think it's ever been changed, or even needed a top-up.

[Tuco]

I recently did this on a 6.0 LS bought used with unknown coolant. This was a suburban with a capacity of 4 gallons.  Each draining got out about 12 quarts, and with a rear heater core, it took a couple dozen gallon jugs of distilled water total.  Good municipal tap water should have been okay, but I used distilled because I'm just that way.

After half dozen drain and fills, running on the roads up to operating temperature each time, you could tell that it was flushed.
Not "i'd drink that" clear, but certainly clear enough to tell that the coolant concentration was nil.

Knowing I had a system full of water made it easy to use 2 gallons of straight coolant (not premix) and top off with a few pints of water, getting the mix right.

[Tuco]

Dexcool is for Cheby’s correct?

Yes.  There were issues with it eating gaskets and not playing well with others.  Some claim that it's been all sorted out, but the memories remain.  I researched it deep enough to decide I wasn't going to risk it for dexcool's extended change interval and went with a universal.

[Bogie]

And buy the concentrate, and add distilled water.
 
I have SO many customers who buy the premix...
 
"My mechanic told me to buy the 50/50."
 
<and I don't say, but I think...>
 
"Your mechanic thinks you are a moron."

[Perd Hapley]

No white coolant after Labor Day.

[zxcvbob]

I recently did this on a 6.0 LS bought used with unknown coolant. This was a suburban with a capacity of 4 gallons.  Each draining got out about 12 quarts, and with a rear heater core, it took a couple dozen gallon jugs of distilled water total.  Good municipal tap water should have been okay, but I used distilled because I'm just that way.

After half dozen drain and fills, running on the roads up to operating temperature each time, you could tell that it was flushed.
Not "i'd drink that" clear, but certainly clear enough to tell that the coolant concentration was nil.

Knowing I had a system full of water made it easy to use 2 gallons of straight coolant (not premix) and top off with a few pints of water, getting the mix right.

I said distilled water, but what I will actually do is take a couple 4-gallon plastic carboys to the grocery store and fill them up with reverse osmosis water from the dispenser.  It's a dollar a gallon cheaper and should be just as good for this purpose.  (I know where the carboys are but will have to search for the caps...)

Not sure if this radiator has a petcock or if I'll need to remove the lower radiator hose.  I think it's supposed to have a petcock.

[zxcvbob]

No white coolant after Labor Day.

  That's an excellent point. Thanks.

[Hawkmoon]

I said distilled water, but what I will actually do is take a couple 4-gallon plastic carboys to the grocery store and fill them up with reverse osmosis water from the dispenser.  It's a dollar a gallon cheaper and should be just as good for this purpose.  (I know where the carboys are but will have to search for the caps...)

They pay you to take their water?

Seriously, the last time I bought distilled water (a couple of years ago, I admit) it was 69 cents / gallon at Walmart.

[zxcvbob]

Distilled water used to be 69¢ a gallon, but it has more than doubled for some reason since COVID.

[K Frame]

Distilled water used to be 69¢ a gallon, but it has more than doubled for some reason since COVID.

Yep, I use distilled for my CPAP and it jumped up to $1.59 for a couple of months before it settled back to $1.39.

Prior to the 'rona, it had been 69 cents a gallon.

[MechAg94]

For home flushing, would it help to run the vehicle with just water for a few minutes to make sure all the lines are cleaned out?


Only mixing experience I can remember is with a screw compressor at plant I was working at.  Someone decided the compressor needed to switch to a different oil.  Then they decided a flush wasn't needed and just drained the old oil from the reservoir and refilled with new.  Later they had to do an unscheduled overhaul as there was some sort of thick material stuck to all the moving parts. 

[HankB]

Distilled water used to be 69¢ a gallon, but it has more than doubled for some reason since COVID.

I use distilled water in my Keurig. It's JUST rose above a dollar last week to $1.08/gallon.

This was a good, timely thread . . . I have a Toyota and a Nissan, and found a couple of gallons of old, green Prestone in my garage. Aside from the age of this stuff (which alone makes it questionable, and makes me wonder why I didn't discard it long ago) confirmation of its likely incompatibility with what's in the radiators now tells me what to do with it - which involves keeping it out of my vehicles. I'll probably bite the bullet and pay extra at the dealers ( ) for truly compatible coolant for topping things off.

I figure it's about time to flush my cooling systems anyway . . . my question is, what's the consensus on replacing hoses as well? The upper and lower radiator hoses of course, and probably the heater hoses as well. The hoses seem to last longer now than they did "back in the day" but I'd hate to have something burst or split when I'm on the road.

[Bogie]

Are your hoses stiff, or squishy. Stiff is good. Gates is thicker than the house brand.
 
Our universal 50/50 is $12.60 including tax for a gallon. The concentrate is a couple of bucks more. The name brand "specific to your car" stuff is $24/gallon out the door for the 50/50 mix.

[zxcvbob]

For home flushing, would it help to run the vehicle with just water for a few minutes to make sure all the lines are cleaned out?


Only mixing experience I can remember is with a screw compressor at plant I was working at.  Someone decided the compressor needed to switch to a different oil.  Then they decided a flush wasn't needed and just drained the old oil from the reservoir and refilled with new.  Later they had to do an unscheduled overhaul as there was some sort of thick material stuck to all the moving parts.

When you drain it, you can't get it all out; maybe half.  Fill it up with water, run it until it's hot (with the heater on), let it cool a little so it's safe to mess with and drain it again.  Fill it up with water again and repeat.  Keep doing this until the coolant you drain out is mostly colorless.

If the thermostat housing is easy to get to you can probably speed this up considerably by removing the thermostat until you're finished; without a thermostat you just run it a few minutes for it to circulate and don't have to wait for it to warm up.

[zxcvbob]

I started this job today.  It should be about cool enough to drain it the second time. 

The coolant capacity is 6.7 quarts, and I can only drain a little less than 3 quarts out, so for the final fill it won't take 3.4 quarts of concentrate but it will be close.  Do I just pour the rest (undiluted) in the overflow tank?  Or do I drain a little out and put *that* in the overflow to make room for the last pint of concentrate?  I'm using Prestone Platinum universal coolant, BTW.  It was only a couple of dollars higher than the regular Prestone, and I should never have to do this again.

There might be coolant drain plugs on the block but I haven't found any.  Damn car is so low to the ground it's really hard to work under without a lift or a pit.

[Tuco]

You might find a chart on the bottle of concentrate, or online, that indicates "lowest temperature" or "freeze protection" for your ratio of 45% coolant to 55% water.
But the coolant ratio will be higher than 3/6.7 until you do several water-only drains and fills.
I suppose it depends on where the vehicle is driven, and most importantly, stored overnight in the winter.
If you park in an attached garage in Missouri you're probably allright. Outside in North Dakota? Siphon out some from the overflow and do some more math.

[zxcvbob]

You might find a chart on the bottle of concentrate, or online, that indicates "lowest temperature" or "freeze protection" for your ratio of 45% coolant to 55% water.
But the coolant ratio will be higher than 3/6.7 until you do several water-only drains and fills.
I suppose it depends on where the vehicle is driven, and most importantly, stored overnight in the winter.
If you park in an attached garage in Missouri you're probably allright. Outside in North Dakota? Siphon out some from the overflow and do some more math.

Parked outside in Minnesota.    I've done 3 water-only drains and refills.  Going to do one more.  44% is probably strong enough for freeze protection here, but not sure I want to dilute whatever anti-corrosion additives more than 50%.  I may hook the exhaust of a shopvac up to the radiator filler to see if I can blow another pint of water out the drain -- if so that solves all the problems.

BTW, the overflow tank on this one is not pressurized.  Not sure what difference if any that makes, other than I have a real cap on the radiator.

[zxcvbob]

After I drained the radiator for the last time, I hook the shopvac up and blew some more out.  I don't know how much because even tho' I had a hose on the petcock it went everywhere.  But I was able to get 3 quarts of antifreeze concentrate in the radiator.  (that was a long slow process because I couldn't find an air bleed vent on top of the engine or thermostat housing)  And I put a pint of AF in the overflow tank.  I've driven the car a couple of times, let it cool down, then used a turkey baster to transfer coolant from the tank to the radiator.  Eventually I'll have all the air out of it.  I went ahead and dumped the rest of the gallon of concentrate into the overflow tank. Eventually I'll need to top it up to the fill line with water.