Radiator flush...

[MistahYebba]

I have a bad mix of water and coolant in my system due to an overheating problem I had about 3 weeks ago.

My system is probably 80% water and 20% coolant. I want to flush it all and start from scratch.

I have 1 gallon of pure coolant, 1 gallon of distilled water, and 1 gallon of 50/50.

Someone please be specific about the steps I must take to flush my radiator with a garden hose without that T-connector or any additives.

Step by step would be greatly appreciated!

 

[natenkiki2004]

There's this:
http://www.explorerforum.com/forums/showthread.php?t=251416

I think you'll need more coolant though, unless you have the 2-row radiator but even then... you should have more on hand, just in case.

Backflush the heater core too.

To sum it all up, take your heater & radiator hoses off and spray water as much as you can in/out the various ports and holes in the cooling system. When it ALL runs clear, hook it up and start filling. Once full, pre-burp the engine by squeezing the upper radiator hose with both hands, multiple times. You'll hear and feel it burp. Add coolant to the overflow tank and run the engine, get it warmed up, maybe take it for a drive and let it sit. Once it's cool, you'll see that the overflow tank may be emptied, fill it up to the line and check it again after driving.

 

[MistahYebba]

Thanks for your reply.

That thread was pretty thorough. Turns out my truck already has one of those Prestone things attached to the heater hose, so I guess the previous owner installed it which makes things easier..

However I don't plan on using the additive that he mentions in his post... which is just a "bonus" cleaning I would imagine.

Also, he didn't really explain how to refill it.

What do I do with my 1 gallon of pure coolant, 1 gallon of distilled water, and 1 gallon of 50/50?

Guy at the auto parts store said first put the 1 gallon of pure and 1 gallon of water in there..... but if you just use your head you're realize... then the mixture would be way off? Then it would be 1 gallon of pure antifreeze and like 2 gallons of water (cause there will be water in the system already after the flush?)

So where do I refill it from and in what order and in what amounts?

Ugh radiators suck. I'm new to all this stuff if you can't tell.

 

[natenkiki2004]

Don't stress about it that much, it's not an exact science. If you read the back of the coolant jugs, you don't HAVE to have an exact 50/50 mixture. More water means better cooling but the chance for boiling and freezing go up. More coolant means a bit less efficient cooling but more high and low temp protection.

I tend to lean towards a higher ratio of coolant but aim for 50/50. If you need to "top off", do it with straight coolant. For example, once the rad is full and the system is bled, fill the overflow reservoir up with straight coolant.

If you REALLY want to be careful, park the vehicle facing downhill, this should help the water you use for flushing drain out of the block and heater core. Fill the system up best you can, start the engine and move the vehicle so it's facing uphill and has an easier time burping.

Having done this process already, I wish I would have run the Prestone Flush fluid, just for peace of mind. What I would suggest is to drain out a bit of what you have now, and add a bottle of that fluid. Then run the engine up to temp a couple of times over the course of a day or two. Being that you're in Florida and it's summer, I'd be hesitant to actually drive it and put a load on the engine with straight water in it. After a couple of days, the fluid should be noticeably dirty, drain it out and start flushing and fill it up.

Also, if it hasn't been done in a while, you might opt to replace the hoses for good preventative maintenance.

 

[MistahYebba]

But everyone always says you shouldn't leave tap water in your system as it has a ton of minerals that can build up calcium or rust?

So how is it that people do flushes with garden hoses? Doesn't that leave a ton of garden hose water in your engine block since you can't really "empty" it all out?

What's the secret to that?

And exactly how much water am I looking at to be in the engine block? I kind of need to know this so I know which fluid to start adding first :/

Let's say I do the flush and that leaves 1 gallon of tap water in the engline block..

Adding 1 gallon of pure antifreeze and 1 gallon of distilled water would leave me with like 66% water and 33% antifreeze.

Since my engine gets a bit hot.. the water would boil away within a week!

and remember I only have 1 gallon of pure antifreeze and 1 gallon of premixed 50/50 at my disposal.

 

[natenkiki2004]

Like I said, there's hardly any water left in the engine when the hoses are removed and you let it drain. If you're that concerned about it, pour some distilled water in and let it drain out.

But really, the amount of minerals and stuff in a cup of tap water that might be left in the engine, it's hardly anything. The additives in the coolant will be more than adequate to combat any minor residue. There's rust inhibitors and all kinds of goodies that will keep the cooling system clean. If you think about it, there's vehicles running the factory coolant and the water pump rusts out or you just look and see the coolant turn brown (not milkshaking, that's different). You will never 100% stop rust. Besides, mineral residue won't make your engine rust away. Calcium is actually kind of good, it's a big additive in oil, it's a cleaner. What you don't want is corrosion but that only really matters in the radiator where it can clog the tiny passages, that's the main reason for doing a thorough flush.

 

[Bobmbx]

Since my engine gets a bit hot.. the water would boil away within a week!

and remember I only have 1 gallon of pure antifreeze and 1 gallon of premixed 50/50 at my disposal.

That means you can have 3 gallons of 50/50. Pour the pure coolant in first, then pour in a gallon of water. Top off with the 50/50 as needed. Your system is rated to hold 1.95 gallons total, not counting the reservoir. If you have AC, its about 2 1/4 gallons.

If you're losing water, you have a leak. Until you find and fix the leak, you're wasting time and money on all this.

The ratio is not important. You can run pure water, and some board members do, without boiling over. That is, as long as your system is holding pressure. See my first comment. If you live where it can freeze, then you need anti-freeze.

I doubt anyone on this board can tell you what the exact ratio of their coolant is right now. As stated by others, coolant comes with all sorts of additives to keep your system from forming heavy, hard deposits which clog the radiator, so some is better than none. Tap water is fine, although I wouldn't use well water unless you know whats in it (hard, soft, iron, etc..). You may be thinking about batteries, which are more susceptible to mineral deposits.

 

[MistahYebba]

Thank you for your helpful response!

I'll do a standard flush; then a Prestone Additive flush; then another standard flush or two...

then top it off with pure coolant and the rest of the way with distilled water.. run it around for a bit and then top it off with 50/50 as needed.

One question though.. during my flush(es), how is it effective at all if the thermostat is closed? Wouldn't the water just back up with the thermo closed?

Also; a few times I've driven it I can hear bubbling/boiling in the overflow tank.. are you sure that isn't enough for water to "evaporate" away over time eventually? Especially if it's like 90% water in my system?

You're probably right about a leak but it must be internal cause my ground is bone dry.

 

[RangerX]

Your owners manual will tell you the cooling system capacity. Whatever the amount is, divide the number in half and use that much antifreeze. Then add water until full. Then you'll have a 50/50 mix.

 

[natenkiki2004]

There's a few reasons why you'd hear coolant bubbling in the overflow;
- Combustion gasses in coolant (very serious issue)
- Faulty radiator cap (cheap fix and will help cooling capability)
- Severely overheating engine (don't run the engine like this, this will NEVER happen normally)

That said, just drain a bit of coolant out then add the bottle of Prestone Flush. You don't have to fully drain what you have, especially if it's fresh/recent.

 

[larrydd999]

If you're going to open up the cooling system anyway, unless you've done this recently replace ALL of the hoses, the thermostat, and the radiator cap, and don't go cheap on the parts. Once you've finished and are back on the road, you'll be glad you did. Also, if you haven't opened the system yet, try to get a pressure test to find out if you do have a leak (internal or external). If so, find and fix it before you start draining and flushing. I purchased a pressure tester because of the number of vehicles I have, plus two marine diesel engines. It gets used regularly as a preventative maintenance tool.