Coolant to water ratio

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I did search and read here but I can't find the exact info I need. Some of you here may know I replaced my water pump last weekend. I had some parts problems and had to take it all apart and install a new pump from a different parts store. Everything is all put back together now, and I believe I have solved a couple of leak problems it had.

My truck has a 14.5 quart cooling system capacity. When I started on the job the first time I drained the system by remvoing the lower rad hose. I can't find any drain on the rad itself. I don't know how much coolant drained out that way. Then more coolant drained out when I took the water pump off the front of the engine. I don't know exactly how much it was. Then when I put it all back together the first time I added a gallon of plain green coolant from Autozone. Then I added about half a gallon of distilled water. I put some 50/50 premixed coolant I already had in the overflow tank. Engine ran OK but I had leak problems with the new water pump.

I put on a new water pump on Monday. I put in another gallon of green Autozone coolant and about half a gallon of the coolant/water mix that I drained out when I took the water pump off for the second time. The coolant was new so I drained it into a clean drain pan so I could re-use it. I added a small amount of distilled water over the next 2 days to bring the level up to the bottom of the fill neck.

I need to know what is this ratio of water to coolant? I think there might be too much coolant and not enough water now. My truck runs OK now but seems to be sort of holding back a little. I filled up the gas tank today and am off by about 1 MPG too. I would guess when removing the water pump and the lower rad hose it drained about 2 gallons out of the system. I have no way to know for sure because on both times when I removed the lower hose and the pump, a lot of what came out splashed on the garage floor. It was a huge mess.

Sorry for such a long post but I wonder if my coolant to water ratio is correct. Service Manual calls for 50/50, I think it's more like 70/30 now, maybe even more than that and I am worried it will cause problems with my engine both internally and in performance/MPG. The truck ran better before I replaced the water pump. Plus it had more condensation out the tail pipe and for a longer period of time after a cold start in the morning.

Is there a way to test the ratio and be sure or should I just dump it all again and do it over one more time? There's a good honest garage down the street, I am seriously thinking about having them just do a BG power flush on the coolant. Then I should know for sure that I have the right coolant/water ratio.

Thanks for any help or ideas. I just want to be sure I have this done correctly.
 
Buy a cheap hydrometer and it will tell you the concentration of coolant in the system.
 
I don't think the ratio of coolant you have would effect your MPG at all. I would be surprised if a your water pump took that much torque from your engine.
I've spoken with guys who live in North Dakota and run 100% coolant in their system, or pretty close to it, and never heard an argument about MPG and coolant.

The hydrometer is a good idea.

In my opinion I would rather have to much coolant than too little.
 
Running 100% coolant is not a good idea from a freeze standpoint. Water and glycaol form a eutectic that maxes out freezing point depression somewhere around 65% coolant/35% water.

Many textbooks of chemistry use this question: Why is it not a good idea to run 100% ethylene glycol coolant? Answer: Glycol freezes around -13 C.

The freezing point of an anti-freeze/coolant solution depends on the concentration of the solution, and rises when the ratio of antifreeze to water exceeds 60%.



With winter approaching, most of us have begun to think about checking our antifreeze. If we're "good" down to, say, 20 below, it's probably wise to put in some more. How much? Well, on the back of most antifreeze cans or jugs, there is usually a table explaining the freezing points of different concentrations of antifreeze and water. Almost all of these tables show values down to about 60 below with a half-and-half mixture, but go no further. That's a pity, because it is at that point that strange things begin to happen.

It's not funny to the poor guy who wants to make really sure this winter, and with a "what the heck" attitude, fills the cooling system with pure antifreeze. He will be the one walking back into the house some frosty morning when its 10 below, shaking his head because his car radiator is frozen solid.

Thom Wigle of Dow Chemical in Ontario informs me that his office receives several hundred complaints each winter from irate customers complaining that their antifreeze is "no [censored] good." A typical story is that the customer was using a Dow product undiluted and their engine froze up at around zero.

Actually, this is to be expected when one considers that ethylene glycol, the principal component of most antifreezes, freezes at 8 degrees above zero, Fahrenheit. It is only when water is added that the freezing point is depressed. The freezing point of an ethylene glycol and water mixture drops rapidly as the concentration of glycol is increased to a mixture of about 60% antifreeze and 40% water. Around that point, an abrupt turnabout occurs, and as more antifreeze is added, the freezing point rises almost as fast as it had previously dropped.

It's clearly a case of what you don't know can hurt you, but I have never seen an antifreeze container with an explanatory note to this effect.

Glycols do not have sharp freezing points, and even below the freezing temperatures, a slushy solution exists which will still flow. In the never-never transition zone around -60°F and 60% glycol, the mixture can either crystallize like water (particularly when "seeded" by a crystal and agitated) or set to a glass-like solid with no orderly internal crystalline structure. Either way, the result is the same, and thawing measures including strong language are prescribed.
 
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Thanks for the replies. I did some math here and I think I had 2 gallons of coolant and water left in the engine each time after I drained the radiator and removed the water pump. I say this because at 14.5 qts total cooling system capacity, I had to add a gallon of straight coolant, plus half a gallon of water the first time, and the second time I added another whole gallon of coolant and about half a gallon of 50/50, plus maybe half a quart of water over the next few days. Subtracting 1.5 gallons from 14.5 quarts (3 and a half gallons) I get 2 gallons left over.

So figuring the amount of coolant that remained in the engine was perfectly mixed at a 50/50 ratio of coolant to water, then what I added the second time around probably brought the final ratio back up around between 50/50 and 60/40 coolant to water. I only had one gallon of straight green antifreeze on hand and it took the whole bottle plus a half gallon of what I think was pretty close to half coolant and half distilled water.

Please correct me if I am wrong on my figures. Now that I have thought about it I think I have closer to a 60/40 mix in my cooling system now. That shold be OK, especially in the Florida heat. I'm not worried about freezing the block, we don't get that here.

I could be worried about nothing here. My MPG could be down a bit due to running the truck in the garage for probably a total of an hour or so, maybe even longer when I was burping the system and letting it run while adding coolant and checking for leaks. The MPG could also be down because I used a different gas station too. I wanted to try the new Marathon station up the street and they had a good price. The MPG could also be due to my new tires dropping it down just a bit. I need to monitor the MPG for another tank or two but it was unsettling to see the worst MPG I have had only after changing the water pump and adding coolant. I filled up at Shell this afternoon coming home.

The performance/power problem could have been due to the cold temperature here this afternoon on my way home, it was about 55 degrees I guess, and for us that is cold, plus there was a pretty strong wind. I had not felt any performance decrease until this afternoon when I was headed home.

I'll pick up an antifreeze tester this weekend just to see if I am right. Today I had read some online horror stories about improper coolant to water mixtures and it got me to thinking and wondering if my own ratio was correct. What really makes me wonder about it is I have more condensation from the tail pipe in the morning now. It still dissipates normally after driving half a mile or so but it spooked me at first. I thought I had a blown head gasket or something when I first saw the condensation after installing the new water pump.

Thanks for your help here. Please correct me if I am wrong on this.
 
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Would this refractometer also work for coolant used in grinding equipment?
 
Originally Posted By: doitmyself
If you can find a shop that has a coolant refractometer, you can get a very accurate reading of your coolant %.

They work so much better than the hydrometers.



^^^^^This is what the detailed Helms manual for my car says to use, exclusively!
 
Originally Posted By: SuperDave456
I don't think the ratio of coolant you have would effect your MPG at all. I would be surprised if a your water pump took that much torque from your engine.
I've spoken with guys who live in North Dakota and run 100% coolant in their system, or pretty close to it, and never heard an argument about MPG and coolant.

The hydrometer is a good idea.

In my opinion I would rather have to much coolant than too little.


You can't run 100% coolant...it gels up and won't circulate. Guy at work tried that and burned up his motor.
 
^ Yup. About 70% coolant / 30% water gives max freeze protection. More than that, and the freeze point actually goes up, as well as the risk of it gelling.
 
Thanks again for the replies here. I will buy a coolant tester and see what it might tell me and then see if I can try to figure out what the approximate coolant and water percentages are.

Looking down the radiator fill neck, the coolant in there looks to be a darker green than what I drained out when I first removed the original water pump. It looks OK to me but I guess trying to judge coolant condition by color is the same as trying to judge the condition of your oil by the color of the oil.

Truck is running fine, I just want to be as sure as I can that the mix is OK. I don't need to worry about sub-freezing temps but it does get very hot here in the summer, 90 degrees to over 100 degrees with high humidity from June through about the end of October. In another month or so we will start to have everyday high temps of 85 and then it only goes up from there. I don't want to overheat or blow a head gasket because the coolant mix is wrong.

I didn't get to check the coolant today. After I do check it if it looks to have too much water in it I will remove the lower radiator hose from the pump and drain out some of the coolant/water mix. I can drain it into a clean drain pan, then measure that out into a gallon water jug and put back in any amount over a gallon to be sure I drain out just a gallon. Then I can put back in a gallon of distilled water. I think that will bring it back to as close to 50/50 as I can get.

I may be worried about nothing here. I do need to test the coolant that's in there first, then I should know if anything needs to be changed. Thanks for all your help here.
 
Originally Posted By: Warstud
Originally Posted By: SuperDave456
I don't think the ratio of coolant you have would effect your MPG at all. I would be surprised if a your water pump took that much torque from your engine.
I've spoken with guys who live in North Dakota and run 100% coolant in their system, or pretty close to it, and never heard an argument about MPG and coolant.

The hydrometer is a good idea.

In my opinion I would rather have to much coolant than too little.


You can't run 100% coolant...it gels up and won't circulate. Guy at work tried that and burned up his motor.


Not only this but the water is what does the actual cooling. Not the coolant. Straight coolant is just as bad for actual cooling as water is for freeze protection.
 
Originally Posted By: Warstud
You can't run 100% coolant...it gels up and won't circulate. Guy at work tried that and burned up his motor.

It happened to my friend as well. He blew a head gasket.
 
Originally Posted By: Kestas
Would this refractometer also work for coolant used in grinding equipment?


Of course; you just need one with the correct scale. Our canmaking machines have a 3.5% specified coolant level and our refractometer is a 0 - 10% model. Also gives a nice visual indication of the amount of tramp oil as the cutoff line becomes gradually blurrier with a higher percentage of oil.

Originally Posted By: rslifkin
About 70% coolant / 30% water gives max freeze protection.

I don't disagree in theory, but in practice different coolants have different percentages to get maximum freeze/boilover protection. Check the coolant's TDS for details.

I tend to refill the cooling system with this mix as it allows future top-offs with straight distilled water.
 
I went today at lunch and bought the Peak antifreeze tester at a nearby AAP. I came back to work and let the truck cool for 3 hours, went out in the parking lot and checked the coolant on my break. The needle on the gauge pegged, it went past the mark for freeze protection to -45 degrees and it went past the mark for boiling protection at 265 degrees.

At 50/50 mixture it should have stopped around -34 degrees and boiling at 255 degrees. Seems to me the coolant to water concentration is way off. I am going to pull the lower rad hose tonight after the truck cools off when I get home, drain a gallon of the coolant/water mix out and add a gallon of distilled water, and check it again after that. I do not want any overheating problems. And it seems the engine is way too cool, the heat takes longer to get hot and my MPG is down. Something is off somewhere and I believe it's the coolant to water ratio.

Any further ideas or info is greatly appreciated.
 
Take a small dispoable cup and mix coolant and water together to make 50/50 and use the tester . Use that as your reference point for the tester. Is it possible that the amount of coolant in your overflow tank is different than in your system. You might get a different reading taking it from the radiator cap. Also I believe with more antifreeze than water your car will run hotter. I wouln't drain out more than 2 Quarts at a time. Jimmy you are on the right track and don't sweat it
 
Well I hope I have it fixed now. I drained out the radiator and what came out of the pump by disconnecting the lower radiator hose. My radiator has no draincock on it. I caught 95% of what I drained out in 2 clean drain pans, measured it into an empty gallon antifreeze jug, filled it up and had maybe half a pint more left over.

I added a gallon of distilled water and ran the system to burp out the air. I had the front of my truck up on jack stands and ran it 4 times with the heat on full blast to circulate the coolant and get the thermostat open and burp the system. The heater got hot pretty fast, just like it did before I replaced my water pump last week. It also didn't have near as much condensation as it did last Monday after I had installed the Autozone water pump, even though it's probably 45 or 50 degrees tonight and I had the garage door open the entire time.

I kept checking the coolant level in the radiator fill neck and kept adding water and some of the mix that drained out tonight. I got it to where the needle on the tester points right at -34 or -35 degrees on the freezing side of the tester. Turn the tester over and it reads right at 265 degrees for overheating protection. According to the tester, that corresponds to a 50/50 mixture of water and coolant. This was when the coolant in the radiator fill neck was warm, not cold. I let it cool off nearly completely and checked it then, the readings were lower. But when I let the engine cool only until it had semi-lukewarm coolant it read right where it should be. I checked it 4 separate times and I believe the coolant to water mix is correct now. That's what I am going with and I am not messing around with it any more. The color of the coolant is a lot better now too.

Now another problem showed up tonight. Now I have a pulley or a bearing somewhere on the front of the engine squealing. I thought maybe I had splashed some water or coolant on one of the pulleys etc up front, but it still squeals even after a 1 mile test drive around the block and back. The faster I go the faster the squeal is. I dunno what it is. I pulled the belt part of the way off and the alternator, idler and tensioner pulleys all turned fine by hand and made no noise, but that is the area where the squeal is coming from. I was too tired to completely R&R the belt again tonight. It was squealing in the garage at idle while I was chceking the coolant, when I got back from my test drive it was just barely squealing at idle in front of the house, but would squeal again if I gave it the throttle.

The belt is a year and 20K miles old I guess. The squeal could be the belt, but it wasn't doing that before tonight when I changed the coolant to water concentration. The edges of the belt are a bit frayed with short little threads sticking out here and there, that might be from the play in the old water pump pulley bearings. Maybe the new water pump is squealing because there is less coolant to lubricate it now.

The belt I have now is a Carquest belt, and I can usually get 2 years out of a belt. If it still squeals tomorrow after I get to work I'll try a new belt and go from there.

Thanks to everyone who replied and helped me out on this. I do appreciate it. I sure hope my coolant and water pump problems are over. Now I just have to fix this new squeal.

Thanks.
 
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