Subaru Coolant

[ktdenali]

I think you're right. there is a bunch of should've-would've-could'ves on Subarus part. It has been an apparent problem way too long.

 

Unfortunately somewhere down the line they are probably trying to meet standards set by people who don't care about good engineering as much as money.

Some mechanics say it is hard to NOT have head gasket issues with any aluminum cast engine blocks. Not just Subaru. But I am not an engineer to know anything about that.

 

Anyway, besides this problem I am still sticking to Subarus. They're great cars, absorb a lot of beating.

[ktdenali]

ok my mechanic gave me a new radiator cap just to see if the one on there was faulty. I took the Subi on a trip for about 300-350 miles over the course of 3 days. I kept my eye on everything.

 

I checked the reservoir on the first 40 miles of the trip and it was bubbling like boiling water. Got to my destination and it did the same thing as before when I checked the cooled down engine - reservoir coolant level high, radiator low.

same conclusions:

-no loss of coolant anywhere

-no white smoke through exhaust

-no leaks anywhere on the engine

-no overheating

-no engine oil/coolant mixing

...but lots of bubbles in the reservoir after driving it long enough.

 

I tried something my mechanic suggested. When got home after driving it 140 miles, I did not shut the engine off. There were bubbles, but if I revved up the engine the bubbles intensified.

 

Is this a sure sign of a head gasket leak and the bubbles are combustion gases or should I be looking at other options before we scream HG?

 

I am scheduled to get it done Wednesday/Thursday.

 

What do mechanics out there think?

 

(at one of rest/check stops along the interstate a car mechanic came and asked what I was doing. He said even though I had bubbles he did not think it was HG, cause I had no overheating, white smoke, or coolant oil mix etc.

I said maybe not yet.)

[idosubaru]

test for combustion gases in the coolant? auto parts stores sell kits to do it yourself or any mechanic can do it.

[Mike104]

test for combustion gases in the coolant? auto parts stores sell kits to do it yourself or any mechanic can do it.

 

Gee, didn't I say that in post #8? and someone else mentioned it in post #24 and gary above. Is a good way to rule out HGs

[idosubaru]

Gee, didn't I say that in post #8? and someone else mentioned it in post #24 and gary above. Is a good way to rule out HGs

that's why i put a question mark, wasn't sure if maybe he did it already but didn't say yet? that would probably be the most helpful piece of info. it's going to pass a compression test, most of these do, so don't bother doing that.

[nipper]

I checked the reservoir on the first 40 miles of the trip and it was bubbling like boiling water. Got to my destination and it did the same thing as before when I checked the cooled down engine - reservoir coolant level high, radiator low.

same conclusions:

-no loss of coolant anywhere

-no white smoke through exhaust

-no leaks anywhere on the engine

-no overheating

-no engine oil/coolant mixing

...but lots of bubbles in the reservoir after driving it long enough

 

Head Gasket

 

SUbaru does not burn coolant on HG failure

HG failure is internal on this year

May or may not overheat

May or may not mix fluids

[ktdenali]

I have not done combustion gas testing in the coolant. I did not know how expansive that would be and how reliable to DIY.

Something tells me the mechanic won't do it either.

When I told him the latest after we put the new radiator cap on, he was just smiling and nodding. Doing a HG today, tomorrow, and mine is next inline:-)

 

The fact that after a longer drive the bubbles are constant and with revving the engine the bubbles intensify, I think that has to be it. Where else could gases come from?

 

Anyway. Even though it is going to be costly he will overhaul that engine pretty good, replacing a lot of parts as well as smooth the head surface out.

 

Hope the car will run better...

 

This forum is awesome, brain stimulating. I learned more about Subarus not being a mechanic than any book could tell me.

Edited July 13, 2010 by ktdenali

[idosubaru]

yep it's headgasket, suggested the test in case you wanted more evidence. there's still mechanics out there unaware of EJ25 specifics.

[ktdenali]

thanks!

 

I do think that test is a good idea, but I am convinced by just what I have seen and hear from you guys.

 

One thing I am still kind of confused on. Someone said once that the 25D and 251 first phase engines have internal leaks, while the second phase 252's have external leaks (no overheating)

 

I guess maybe we cannot generalize them. It is unpredictable.