Subaru Coolant

[ktdenali]

I have a 2000 Outback ltd. 136000 miles. I noticed the strangest thing this morning I have ever seen. I drove it last night for about 80 miles. Everything looked normal (engine temp etc.) This morning all cooled down I checked the fluids

My coolant overflow reservoir was way too full and my radiator was way low. I poured the excess fluid back into the radiator, and it seems like the radiator was needing the exact amount that was excess in the overflow tank. So I am not missing any coolant. No leaks anywhere on the engine. No sweet smell or any sign of coolant leak.

I just recently had a faulty thermostat issue, which I changed (replaced a cheap aftermarket thermostat with an OEM Subaru part), as well as a new radiator cap. That was 5000 miles ago. The car has been running great since and that solved my previous problem of fluctuating temperature gauge.

 

What can cause my overflow tank to be way full and the radiator low? Do I have another thermostat issue? I have not warmed up the engine to compare the upper and lower radiator hoses yet, but it maybe the next thing on my agenda.

Anybody? ideas?

[idosubaru]

Could you please describe your symptoms before you replaced the aftermarket thermostat? What problems did it cause and how?

 

Your current issue could be the radiator cap - it controls the flow between the overflow tank and radiator. It's cheap anyway and probably good preventative maintenance on a 10+ year old vehicle so I often just replace them. They're rated by PSI and most stores should have one for yours.

 

EJ engines are notoriously hard to bleed so if the cooling system has been opened or low for any reason it could have an air bubble somewhere in it. They cause random overheating. Nose up and lots of squeezing of the radiator hoses helps, though I haven't had this issue on the Phase II stuff yet and the older stuff had a bleeder screw that helped so not sure of any more specifics than that. You can search for the term "burping" here and find lots of info on it because it's fairly common. I had one 97 legacy that kept running hot after i did the water pump and it took forever to get all the air out. My buddy has been driving that car for 60,000 miles over the past 3 years now.

 

Your engine is supposed to have a Subaru coolant conditioner added to it - Subaru sells it specifically for this engine.

Edited July 6, 2010 by grossgary

[heartless]

I just recently had a faulty thermostat issue, which I changed (replaced a cheap aftermarket thermostat with an OEM Subaru part), as well as a new radiator cap. That was 5000 miles ago.

 

he did replace radiator cap, Gary....

 

just pointing it out.

[Durania]

Sounds exactly what my RS did when the head gaskets went.

 

Yeah, I jumped straight to the head gaskets.

[ktdenali]

yes I did replace the radiator cap just 5000 miles ago along with the thermostat.

The symptom back then was a fluctuating temperature gauge. When I drove it uphill, such as up to a ski resort in the winter, my temperature gauge would climb up. Did not overheat at, as it was still in the safe zone, but I did not like it. temperature gauges are supposed to be rock solid.

 

A mechanic suggested it was the thermostat, and he was right. I pulled out a cheapooo and put in an OEM Subaru part. Ever since that problem disappeared.

 

I also suspected the radiator cap, but since that is almost new, I wondering if it could be something else.

 

I have not toyed with the idea of head gasket yet, because I have not seen any of the symptoms that people say can be a head gasket issue.

 

Different engines, react different ways to head gasket problems. This is an EJ252. No leaks in the back of the engine. No sweet smell in the exhaust. No cooling fluid mixed in my oil. Cooling fluid level still solid. Absolutely no overheating.

 

So I am still confused on what can cause this.

[idosubaru]

Fans are both coming on when it's getting hot?

 

You said the fluid levels were different - were there any symptoms like a fluctuating temp gauge?

 

Was the coolant additive required by Subaru on 2000+ models added?

You didn't comment on "burping", you're fairly confident there is no air in the system? Keep in mind these particular engines can be much harder than other Subaru engines to bleed of air.

 

Subaru's have common failure modes because it's a design problem, not just a failed gasket with age/mileage, so they often look the same. The poor design doesn't rule out other failure modes common with age/mileage of any head gasket, so other things are possible.

[Petersubaru]

you have a small leak or opening, drawing/sucking air into the coolant system thus preventing the coolant from the reser. to be returned back thru the rad..problem could be anything from a headgasket leak to a faulty rad cap (the top rubber seal is worn out)..replace the rad cap to start with..pressure testing the system "may or may not" find the problem

[Mike104]

I have a 2000 Outback ltd. 136000 miles. I noticed the strangest thing this morning I have ever seen. I drove it last night for about 80 miles. Everything looked normal (engine temp etc.) This morning all cooled down I checked the fluids

My coolant overflow reservoir was way too full and my radiator was way low. I poured the excess fluid back into the radiator, and it seems like the radiator was needing the exact amount that was excess in the overflow tank.

 

What can cause my overflow tank to be way full and the radiator low? Do I have another thermostat issue? I have not warmed up the engine to compare the upper and lower radiator hoses yet, but it maybe the next thing on my agenda.

Anybody? ideas?

 

While it is a Phase II EJ25 that are more susceptible to external leaks than internal ones like the Phase I your description of what is occurring (fluid transfers from rad to overflow) is how my Phase I started acting when the HGs went. I carried around a large turkey baster to move coolant from the overflow tank to the rad after every trip (when enough time had passed to make sure the engine was cold) until I could get the replacement engine (236k on odometer) ordered, delivered and installed.

 

Best way to confirm HG leak is to use an exhaust gas analyzer or a chemical block test kit to see it there are combustion gases in the coolant. If positive, its likely an HG or other internal engine issue. Its usually a cheap test and is a good pass/fail test. Negative test means look for other issues. Positive test means take off the heads and check for bad HGs.

[ktdenali]

ok I started the car up and got to operating temperatures. Drove it a few hundred yards just to make the warm up faster. there was a lot of trickling sounds of water while driving it.

Came back home, put the front on raps and let it run until the radiator fans cam on 3 times. Since this one does not have a bleeding screw on the radiator I believe the only way to air the system out, is to get it warmed up. There were many many bubbles in the overflow tank and I think I ran it long enough that all the air came out. In the mean time I kept squeezing both lower and upper radiator hoses.

 

It is now in the garage, letting it cool down, so I can open up the radiator cap again and see the situation.

 

No I have never added any kind of an additive to the cooling system. I have only had this car for the last 9000 miles so I have no idea what the previous owner(s) did to it.

 

Conclude and answer some of your questions.

I notice no leaks anywhere

Thermostat working properly, both hoses get hot after a while.

Both fans come on, and I cycled it three times

There was air in the system and I think it's now out.

 

The question is! How did air get in the system? Now that I blurped it, will it remain airless?

[ktdenali]

forgot!

Looking and sniffing around the exhaust, I saw a little bit of water on the ground dripping from the end of the (exhaust) pipe. But it was just clear liquid, water, sweat, which I think is normal.

[ktdenali]

Talked to my Subaru mechanic guy and he said it is probably going to be a head gasket issue.

I guess the only other place I can imagine air getting in the system would be through a radiator cap, but since that is almost new it is very unlikely.

 

Anyone? Any further ideas, suggestions from the symptoms I described?

Thanks

[Durania]

Same thing happened to me in January. I had zero running issues, zero coolant and oil mixture, zero over-heating. What happened was the coolant jacket was getting pressurized and causing mine to come out the overflow and spew all over the engine.

[nipper]

Sounds exactly what my RS did when the head gaskets went.

 

Yeah, I jumped straight to the head gaskets.

 

 

Thats where I would go too.

 

 

 

nipper

[ktdenali]

I am not 100% sure what you mean by the coolant jacket getting pressurized???

 

I have NO coolant anywhere on the engine. neither underneath the car, or anywhere outside. In fact it's all where it was supposed to be, AT THIS POINT.

 

I just got air in the system somehow, and not sure where.

 

Even though there is a very small chance of it, my mechanic said we will try a new radiator cap first, just to see if maybe the new one I put on there is defunct. if that does not resolve the issue, it maybe a head gasket.

 

Anyway, if you could tell me what you meant in your comment ("coolant jacket") I will look into that too.

Thanks a lot

[nipper]

Coolant jacket getting pressurized = combustion gasses pressurzing cooling system = bad headgasket

[Petersubaru]

Coolant jacket getting pressurized = combustion gasses pressurzing cooling system = bad headgasket

..if that is in fact the case..the subi conditioner will not work here

[ktdenali]

It all makes sense now. I will get her done but will try the new radiator cap first. I am very skeptical about that though. I guess our Subi mechanic is trying to save us money, just in case it would be a faulty cap.

 

I did not think the subi cooling conditioner would do anything.

I do wonder though if that additive is still necessary after the new head gaskets have been installed?

[nipper]

It all makes sense now. I will get her done but will try the new radiator cap first. I am very skeptical about that though. I guess our Subi mechanic is trying to save us money, just in case it would be a faulty cap.

 

I did not think the subi cooling conditioner would do anything.

I do wonder though if that additive is still necessary after the new head gaskets have been installed?

 

 

It is basically chicken soup for soobys, it couldnt hurt.

[Durania]

Sorry to be the bringers of bad news. We see these types of posts every week. I have been there, I know exactly how frustrating it is.

 

Best thing you can do is fix the head gaskets and drive the car for another 100,000 miles.

[ktdenali]

I am not terribly frustrated 'cause I knew it was coming.

It was a matter when... NOT if...

 

I kick myself for buying a used Subaru, in which the head gasket has not been dealt with. But since the dealer who sold it to me had no idea of previous maintenance records, I did not know. I was optimistic that it's been dealt with at 126k (when I bought it).

 

Subaru makes great cars, and I will probably stick with Japanese cars for the rest of my life, particularly Subarus.

 

But I wish they (Fuji Heavy Industries) would have dealt with an obvious problem they have head since the 2.5 engines came in (1996). The 2.2 was literally bomb-proof.

[Durania]

They ran an extended warranty on the head gaskets and were warrantied to 100,000. Mine just happened to blow at 120,000. About the only fix they tried was the coolant treatment.

[nipper]

I am not terribly frustrated 'cause I knew it was coming.

It was a matter when... NOT if...

 

I kick myself for buying a used Subaru, in which the head gasket has not been dealt with. But since the dealer who sold it to me had no idea of previous maintenance records, I did not know. I was optimistic that it's been dealt with at 126k (when I bought it).

 

Subaru makes great cars, and I will probably stick with Japanese cars for the rest of my life, particularly Subarus.

 

But I wish they (Fuji Heavy Industries) would have dealt with an obvious problem they have head since the 2.5 engines came in (1996). The 2.2 was literally bomb-proof.

 

 

Lets stop beating up subaru on this. Every Mfg from this period on have at least one engine with a HG issue. With subaru they only use really two or three engines, with the 2.5 built to the very edge of what the engine can do.

 

Some mfg told customers to go screw. Chrysler comes to mind as well as Range Rover (their engines would overheat so bad the cylinder liners would shift). Others came up to bat, and others as they realized how big the issue was came around.

 

136,000 miles and a failed headgasket is not necassarily something that can be blamed on subaru. The older any car gets the more the chances are of a blown HG. Engine ping and coolant contamination for instance are part of the equation.

 

One of the causes of this was new emissions stds and a hp/mpg war that followed. It takes time to fully test a car for 100K, some use 140K. Test protocol, depending upon the level of failure, requires starting the test all over again.

 

Some just dyno test the engine for X hours, which is not real world driving.

 

The issue was industry wide. The three layer HG was a new design to deal with higher combustion pressures and temps required for HP output and emissions. The materials were not quite up to the job, so they had to be constantly tweaked. Add in an open deck or semi open deck design it just adds to the issues.

 

You make it sound like every HG fails in every subaru, it doesnt. In fact an internal failure for this year is rare. Usually it is an external leak.

 

Without knowing how the previous owner took care of the car, subaru can not be blamed for this one.

 

 

nipper

[ktdenali]

I do not necessarily blame Subaru. I would still buy one after this one, and the years coming.

In fact I bought this one knowing that this was probably going to be an issue.

Maybe not all Subarus have HG failure but from what little I understand a huge percentage of the 2.5's do. Several generations.

 

I do not know enough to blame Subaru for sure. I am just comparing the 2.5 engines to the 2.2's which had no such issues on such large scale.

 

I asked my mechanic about the additive Subaru came up with to solve their HG problems, and most people seem to think that was just a bandaid. it may work but they still are keeping in business by changing head gaskets as a solution.

 

I do no have an internal leak, or an external one yet. But I assume once things get worse it will be an external one.

Edited July 7, 2010 by ktdenali
typos

[Yo'J]

I would say check the hydrocarbons in the coolant for exhaust leaks and the water pipe over the top for leaks as air could be getting in and , seriously, lift the front end up and make sure there is no air bubble sitting in that waterpipe. If you hear water in the heater lines, its a bubble. Some people have posted that they fill from the top rad hose first then the rest of the rad.

I really don't know if your engine has a coolant pipe under the intake manifold that is separate with o-rings, like on my 22 that just had a bad HG, and not part of the block casting. I hear that can pull in air there, mimicking the signs of HG failure. I could smell the exhaust in mine. Good luck!

[mikec03]

I think that we can beat up on Subaru for the head gasket problem! It doesn't appear that they have completely solved the problem with the gen II 2/5 engine [judging from the posts on this and other forums] from 2000 to 2009. As an engineer, I think that's too long. If it was just a couple of years, I could be more forgiving.

 

I'm assuming that the stiffening of the cylinder wall in 2010 will finally solve the problem.