I've also done the at-temp leakdown and it didnt show anything either....except on ONE car.

 

However, eventho the cooling system HC test wont always show it...the coolant does have a different smell to it when its ALWAYS a head gasket.

cant do a coolant pressure test if my coolant tank is split

 

Then how, besides guessing, can you determine if you have a head gasket "problem" if the cooling system won't/doesn't hold pressure? The cooling system can't work anywhere remotely near "normal" if it can't pressurize.

 

Say you have a 195 degree thermostat in there, the operating temperature is roughly 10 degrees hotter, so you are attempting to operate at 205 degrees. Without the system able to pressurize (like a pressure cooker) the coolant is going to boil at 210 degrees, you are, in effect, running a cooling system without a rad cap.

 

Replace the tank then see what is what.

 

Part # 21132 AA010

I've also done the at-temp leakdown and it didnt show anything either....except on ONE car.

 

However, eventho the cooling system HC test wont always show it...the coolant does have a different smell to it when its ALWAYS a head gasket.

 

The leakdown numbers will not show anything. It is the air or coolant being pushed out of the radiator. Depending on how bad the leak is, sometimes you have to keep the cylinder pressurized for a while, but with the radiator topped off and radiator cap off, even a very slight leak will cause a rise in the coolant level.

 

Seems staight forward when you deal with these cars day in and day out. Not so easy for others to notice the difference between the smell of exhaust in the coolant and the smell of just coolant, when they don't know what it should smell like in the first place.

Raveen, the origin of this post is much more than "how to determine wether i have a blown headgasket" It started off with blowing coolant lines left and right. After blowing my heater core. Now my tank is split, and its obvious it was under pressure cause of the bowing involved.

 

Replacing the part and continuing on will not solve my problem... the next thing to blow will be my radiator, or another hose.

 

I guess Im just going to do the gaskets and be done with it.

Not so easy for others to notice the difference between the smell of exhaust in the coolant and the smell of just coolant, when they don't know what it should smell like in the first place.

 

Im a heavy equipment mechanic, i deal with coolant on a daily basis. I can identify the smell of antifreeze, and exhaust in my coolant. I also have a HC tester at my disposal. I guess i've just been blind to the whole ordeal. Usually, when head gaskets blow you burn coolant. Or your car overheats even with a full radiator. And there is almost always a miss-fire on the dead cylinder.

 

However my car runs great. Never runs past normal on the temp gauge... until the coolant is gone. And it doesnt burn coolant as that would/should show out the tailpipe. So I've just been naive about the whole thing and hoping it was just something stupid.

 

Looks like I got a weekend full of work ahead of me :-\

It started off with blowing coolant lines left and right. After blowing my heater core. Now my tank is split, and its obvious it was under pressure cause of the bowing involved.

 

It certainly is not "obvious" and especially not on a 15+ year old car, that may, or probably not, have had a single hose replaced, ever.

 

(and this from a fella with "almost" EXACTLY the same motor, ok, it's older, with 325,000 miles on it, with, surprise, surprise, the original head gaskets)

 

And............being a closed top block (solid deck) you are going to pull the heads and if you do find a "bad" head gasket, you will find a warped head along with it.

When you say Almost and Exactly in the same sentance... what is you mean?

 

Your running a EJ22T as well?

The leakdown numbers will not show anything.

 

Thats what I said. The car that showed a problem was overheated until it would not run anymore. It had a grand canyon crack down the jacket and that cylinder pressurized the cooling system. It was obvious to see where the combustion was going once the head came off.

Usually, when head gaskets blow you burn coolant. Or your car overheats even with a full radiator. And there is almost always a miss-fire on the dead cylinder.

 

However my car runs great. Never runs past normal on the temp gauge... until the coolant is gone. And it doesnt burn coolant as that would/should show out the tailpipe. So I've just been naive about the whole thing and hoping it was just something stupid.

 

Looks like I got a weekend full of work ahead of me :-\

 

This is the BIG misconception about Subaru EJ22 and EJ25 head gasket failures. And the reason people throw so many parts at them before they realize that the head gaskets are bad.

The head gaskets on these engines do not fail the same or show the same symtoms as your average blown head gasket.

 

You said it yourself, "my car runs great". If it had enough combustion leaking past the fire ring to show up on a compression test, it wouldn't run great. If it was buring enough antifreeze is show out the tail pipe, it wouldn't run great.

 

The EJ head gaskets do not leak that bad. It is a small leak, (at the onset of the problem most won't even leak when the engine is cold) which pressureizes the cooling system over time, pushes coolant out, and the engine over heats do to low coolant or air lock.

 

This is why I recommend a cylinder leak down test on a hot engine. You don't really need a leak down tester, just a regulated air supply and compression gage hose that you can conect shop air to. The leak down numbers will tell you nothing. But by pressureizing the cylinder, you can find the leak. The air will make it's way into the cooling system. If the leak is very small it may take a few minutes.

Thanks guys. Im convinced my head gasket is leaking. I just gotta find time and money to repair it. Well, money isnt as big a concern as time. I cant seem to find a gasket set local, and Im lookin at a week if not longer to get one to me. Woulda loved to have it this weekend so I can make use of this 4 day weekend, but i guess thats not going to work.

 

Im going to be getting a replacement coolant tank and install that to get the car back on the road. Once I have my gasket set I'll tear the motor and go through it.

 

Subaruparts.com doesnt list a t-belt set for the legacy. Anyone have any good vendors out there that supplies a complete kit? belt, idlers etc... Might as well do that while im in there.

 

-Brian

ebay has kits.

 

Otherwise, you have to buy each part individually from SUBARU.