To rebuild or not to rebuild (aka where tf is my coolant going?)

[SubieTourist]

Hoping to get a little help about some issues with my Legacy.

'97 Legacy L with the stock EJ22.

It's overheating after 20-30 minutes of driving time. Removing the radiator cap reveals that there is coolant missing from the system, and it is not pulling coolant back out of the reservoir. If coolant is put back into the radiator again, it will run without overheating until once again enough coolant is missing to cause an overheat. There does not seem to be coolant leaking onto the ground anywhere, regardless if the engine is hot or cold. The oil does not seem to have any coolant in it.

After replacing the radiator, radiator cap, and thermostat, I finally took it into a shop, who within the hour told me it was a blown head gasket. I'm not sure how they were so sure, so quickly, unless they checked the coolant for gasses. In contrast to this diagnosis, everywhere I look on this forum people are saying "EJ22s don't blow head gaskets." but an internally blown head gasket seems to fit the symptoms.

Is there anything else I should check? If not, what are the best options for head gaskets?

[1 Lucky Texan]

maybe they pressure tested the coolant system and found a spark plug wet with coolant?

[idosubaru]

3 hours ago, SubieTourist said:

Hoping to get a little help about some issues with my Legacy.

'97 Legacy L with the stock EJ22.

It's overheating after 20-30 minutes of driving time. Removing the radiator cap reveals that there is coolant missing from the system, and it is not pulling coolant back out of the reservoir. If coolant is put back into the radiator again, it will run without overheating until once again enough coolant is missing to cause an overheat. There does not seem to be coolant leaking onto the ground anywhere, regardless if the engine is hot or cold. The oil does not seem to have any coolant in it.

After replacing the radiator, radiator cap, and thermostat, I finally took it into a shop, who within the hour told me it was a blown head gasket. I'm not sure how they were so sure, so quickly, unless they checked the coolant for gasses. In contrast to this diagnosis, everywhere I look on this forum people are saying "EJ22s don't blow head gaskets." but an internally blown head gasket seems to fit the symptoms.

Is there anything else I should check? If not, what are the best options for head gaskets?

 

Headgaskets. Resurface the heads, clean the block face, lubricate the headbolts, and install Subaru headgaskets.
The head bolts are all external, these are one of the easiest subaru headgaskets to do.  
Verify for sure you don't have any leaks - a pressure test of the cooling system or leak down test might show it. Or combustion gas test.

 

It's a gasket. Run one hot enough and any engine ever made can blow a headgasket - no manufacturer can avoid physics. 

The notion that "EJ22s don't blow headgaskets" is just making a point that they are solid engines. 
In stock form, off the factory floor, they do not have a propensity to blow headgaskets without a causative reason.  You can expect nearly 100% of brand new EJ22's to make 150,000 miles without headgasket issues.  EJ25's and EZ engines have a certain percentage of failures, some at low mileages. 

But they're not brand new any more or even close to it. 

I'm a big EJ22 fan but now that they're a quarter century old with lower availability, often unknown histories, low values prompting worse maintenance/more owners, the condition of any one particular EJ22 is much less certain. 

Edited May 16, 2019 by idosubaru

[GeneralDisorder]

They blow. Its happens. Usually between 220k and 280k of natural causes. Or more quickly if abused. One of my loaner cars (1990 Legacy) came to me with blown HG's at only 110k miles. As with anything - it's a gasket and it can and will fail. People that say they don't blow are only repeating what they have heard and likely have experienced only a handful of their own cars and the cars of friends and family. I have a statistical sampling numbering in the thousands and YES they absolutely can and do fail. Just less often than the 25D. 

It's easy to tell and it's easy to diagnose. You look for oily residue in the overflow bottle, you do a cold pressure test, and you drive the car. If there is residue, it holds pressure cold, and overheats after 10-30 minutes of driving anyway - you have a HG failure. 

GD

[el_freddo]

Get into it before you seriously overheat the block. This reduces the hardness of the alloys used in the block, and thus, it’s not as good as it was in the past, even with a new HG. 

Cheers 

Bennie

[sparkyboy]

A couple of notes here, a pressure test (or is it the leakdown test?) One is for the head gasket, the other is for the coolant circuit.

Anywho the test will tell you definitively but does require special equipment. As does the carbohydrons in the coolant test you mentioned.

Try this, but i am not sure if subarus do this, but most cars with a blown gasket on the water side, as subarus tend to do (i have heard of only one "oil milkshake" which is a failure on the oil side of the hg, allowing coolant into the oil rather than the combustion chamber) will spit a whole bunch of coolant right out the filler neck if you crank the engine with the radiator cap once.

These engines are very sensitive to thermostats since its on the bottom of the engine . A long nose one is required and an improperly filled one will cause an airpocket which will cause overheating.

You can see if that is the issue by driving and once she starts to get hot, stop somewhere and feel both radiator hoses to see if they are both the same temp as well as the heater hoses to feel for one that coolant is not flowing through.

Lastly, how long does it take for her to overheat again after you fill the radiator? Right away or a few days? 

One of the two rubber lines for the iacv may be leaking and when the passenger side leaks slowly, it drips onto the exhaust, eliminating all evidence of an easy fix!

Barring that, the hgs are easy, you can just remove the nuts from the motor mount and tilt the engine if you don't want to take the whole thing out.

Oem and fel pro gaskets are fine for these engines, just take care to clean the block super good, i botched a bmw once cause of careless block cleaning.

Might as well get a timing belt kit too unless that has recently been replaced.

A top speed record was set at Bonneville and the driver felt more power inexplicably...

The head gasket leaked just the right amount of distilled water im assuming possibly water wetter for a race engine to make more power similar to methanol injection for turbo cars. In fact the corvair turbo had an option for meth injection. It was just windshield washer fluid and called boost boost or something silly like that. Haha!

I digress. Happy wrenching! 

By the way that shop that looked at your car is incredibly lame if they won't tell you how they came to the conclusion that your hgs need replacing.

Fix them and go back stating the same problem and see what they say, they might be trying to fleece you.

 

Edited May 18, 2019 by sparkyboy