Just out of curiosity, what would you all consider "normal loss" for coolant in about a year's time with, say, 15k miles. My Corolla probably loses about a quarter to half cup from the overflow tank level, and the Forester is probably 1 cup. These are estimates. I know some evaporates, etc. etc. and I'm not concerned, as the loss is minimal either way. Just a "fun thread" that's probably been discussed before.
Normal coolant loss per year?
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Seems normal to me. I tend to do a drain and fill every couple of years, and after getting the tank back to the right level I don't think I've had to touch it until the next time.
My VW had a pressurized overflow tank, I think? I think it was all sealed up. I suspect those systems wouldn't lose anything. The current fleet though has some amount of air circulation, have to figure it will evaporate some off, albeit slowly.
My VW had a pressurized overflow tank, I think? I think it was all sealed up. I suspect those systems wouldn't lose anything. The current fleet though has some amount of air circulation, have to figure it will evaporate some off, albeit slowly.
A properly designed cooling system will lose some coolant by design.
My 6.0 leaks nothing but my son’s 4.8 loses a cup a year. Make sure you have no weepage at the water pump drain hole which will show a stain from evaporated coolant if it leaks. Otherwise small seepage is hard to find and remedy.
depends on if the system has a regular overflow tank or a pressurized one.
My jeeps with pressurized system lose nearly nothing. ie 2 years in still on the full mark when hot.
The 4 subarus with "open" overflow all used enough you needed to add upto a cup per year.
My jeeps with pressurized system lose nearly nothing. ie 2 years in still on the full mark when hot.
The 4 subarus with "open" overflow all used enough you needed to add upto a cup per year.
In a properly pressurized system where everything works as intended, there should not be any measurable loss in 5 years at least.
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I’ve seen around a cup loss over the course of 25,000 miles in both system designs...sealed and unsealed. I would call that “good” or normal.
I think you can expect a little more or less depending on climate and driving tendencies.
I have heard some people say that you should experience ZERO coolant loss, and if you do, you have a leak. I totally disagree with that assessment.
I think you can expect a little more or less depending on climate and driving tendencies.
I have heard some people say that you should experience ZERO coolant loss, and if you do, you have a leak. I totally disagree with that assessment.
why do I have no loss in my jeep? well no measurable amount.
Where does it go in a fully sealed system with pressurized tank?
My subaru's did slightly worry me with the amount they lost but past subarus had HG issues and I had a first year engine. (2011 fb25 in forester)
My Chrysler 4.0L (V6) has a pressurized reservoir. I can't for the life of me keep the coolant at the cold level or hot level. I'll fill it up and within a a week or two it'll drop down to about an inch and a half below it. I don't know where it goes, but it settles down to that lower level (still above any hoses and never empties the tank) and stays there. I've left it for a couple years and it never budges, overheats or gives any indication of actual coolant loss. But as soon as I add coolant to the COLD or HOT marks, it quickly drops back to where it was before.
My experience with unpressurized reservoirs is that if the cooling system is operating correctly, they typically don't budge as long as you don't overfill them. So in a year or two, you'd expect the level to stay the same or very close to what you started.
My experience with unpressurized reservoirs is that if the cooling system is operating correctly, they typically don't budge as long as you don't overfill them. So in a year or two, you'd expect the level to stay the same or very close to what you started.
In the past year my Jeep has lost none. My Escape has lost about 6oz.
Interesting replies about the pressurized systems. I've never had a pressurized overflow tank, or whatever that is. I know, too, that the level in the reservoir fluctuates with air temperature, too. 50 degree day it is higher than a 15 degree morning, it seems.
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If it is sealed and you are seeing the level drop that much within a week ,you either have a leak or the car is burning coolant.
You mean the magic coolant fairy isn't coming and taking it?
The coolant can actually escape through the cap if the system is over pressure, which can happen from being overfilled / not having enough air in the pressurized expansion tank. I've always just assumed the fill lines are a bit off as I've pressure tested the system and verified it's not burning any coolant. Coolant has been at the same level for 2+ years now, so I think it's doing just fine at that lower level.
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My wife’s 6.2 Yukon has dropped slightly from full in the pressurized expansion tank. No idea where it goes but I’ve topped it off 2, maybe 3 times in 67,000 miles. It only drops an 1/8-1/4” or so and doesn’t seem to drop any further like 92saturnsl2 said. No visible leaks and don’t see any noticeable burning or coolant noted in oil analysis.
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I would consider a faulty cap allowing coolant to escape to still be a 'leak".You mean the magic coolant fairy isn't coming and taking it?
The coolant can actually escape through the cap if the system is over pressure, which can happen from being overfilled / not having enough air in the pressurized expansion tank. I've always just assumed the fill lines are a bit off as I've pressure tested the system and verified it's not burning any coolant. Coolant has been at the same level for 2+ years now, so I think it's doing just fine at that lower level.
However I would bet they you do have a leak somewhere, if you are not burning coolant, are you looking for residue I would also look at the head gasket it might be leaking outside of the coolant jacket.
My 11' Chevy Cruze lost a lot of coolant regularly...and you could smell it...my 16' Ford Escape has lost none in the 5 years I've owned it. My 14' Focus did lose a little until I changed the surge tank cap about 2 years ago...haven't lost any since.
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I don’t know, how much do you drive? No measurable loss? And where does it go...evaporation, it is a liquid and it will evaporate even in a closed system. The temperatures coolant is exposed to is extreme, along with the temperature changes. Temperature changes will absolutely cause a rising and lowering of coolant readings, which will give you different readings depending on ambient temperature as well.
But working in the trade for most of my life, I don’t think I’ve ever seen a regular customer not lose something over the course of a year of service (Putting some mikes on the car though). A simple little top off over the course of a year.
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A cap doesn't have to be faulty to lose coolant through it. It's doing it's job if it's letting coolant escape from an overfilled system, or one that doesn't have enough room for expansion under pressure.
As I stated a couple times, the coolant level doesn't budge once it drops a bit, then it settles there and has for more than a couple years now. No loss = no leak in my book.
36000 miles. no loss. not 1/4 inch I made a cold mark on the tank when it was purchased.
all 3 subarus would use inches/year on the overflow, but not sealed overflow.
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