Possible head gasket failure...

[Kowdog]

Greetings all, have a question for you. First, the facts. 1996 outback 2.5 dohc 165k miles, head gaskets replace at 135k miles.Also had new WP, radiator, all TB components, t-stat,plugs/wires.
Here's what has transpired to date. After HG replacement, many miles later,(15K+), all was well till this winter weather set in. Northern Nevada, not to cold,near freezing mostly. Engine would not stay warm after initial warmup and driving to work@8 miles. On the way to work, @half way would drop halfway to cold side,(somewhere between center and bottom). Wife complained "no heat!". So I changed t-stat and started car, and it came up to just under the icon on the Gage, say just under halfway. She drove to her daughters that night,a 60 mile trip with two mt. Passes of @5500' each. Car was fine till the upgrade on the first Pass. She said it got almost to the top of Gage (HOT!) so she slowed down and it cooled down. Happened only going up hill under load, both passes going to, and
Coming home. She had son- in- law check rad level,was low, he topped off, she started home, same deal, hot on grade under load. I check rad level and overflow, this am. No fluid in overflow,low radiator level.tail pipe
Shows black soot,no grey color, no grey in oil, oil level normal.I a lost as to what happened. Till I changed
The T-stat, fluid level never changed. I refilled the anti-freeze that was drained when I changed the t-s
Tat, topped off the overflow,brought it up to temp, shut it down, and re-checked all the levels, all good!!! Any input would be
Most
Appreciated. Thanks...

[subiesailor]

HG failure can happen any time and the quality of the work that goes into the HG job has a direct impact on if it holds or fails sooner than later. I had Toyota rebuild a V6 three times total block strip down and new heads all three times I got rid of it after the third time given it was clear even Toyota couldn't get their own engine right.

[AWDFTW]

What brand tstat did you use?

[bstone]

Overheating while driving up a mountain? If you used a Subaru t-stat then you likely have a bad head gasket. Sorry. :/

[Bingo6104]

Well instead of starting another thread, I am hoping to just join in here..
My stats 1997 Subaru Outback 2.5... 190,300 miles

Not any problems till now

The other day the car overheated on the way to work...

Well I done the normal got a reg themo stat and changed it out, filled the coolant up.. that failed..

Done some googling and found out that the cars prefer the genuine part, so i got the Subaru thermo/gasket and radiator cap from the dealership.

I followed this
Draining and Replacing Coolant and Thermostat

Ok ,thought all was great temps stayed stable for about 50ish miles done in the past day and a half then it started to over heat again. Except this time its spewing out into the over flow.. So this week i have spent at least $80 on this and I am wondering what is wrong? No white smoke out the exhaust...nothing in the coolant, no coolant in the oil.. Im just at a loss on what to do..

[bstone]

Originally Posted by Bingo6104

Well instead of starting another thread, I am hoping to just join in here..
My stats 1997 Subaru Outback 2.5... 190,300 miles

Not any problems till now

The other day the car overheated on the way to work...

Well I done the normal got a reg themo stat and changed it out, filled the coolant up.. that failed..

Done some googling and found out that the cars prefer the genuine part, so i got the Subaru thermo/gasket and radiator cap from the dealership.

I followed this
Draining and Replacing Coolant and Thermostat

Ok ,thought all was great temps stayed stable for about 50ish miles done in the past day and a half then it started to over heat again. Except this time its spewing out into the over flow.. So this week i have spent at least $80 on this and I am wondering what is wrong? No white smoke out the exhaust...nothing in the coolant, no coolant in the oil.. Im just at a loss on what to do..

Make sure you burp the radiator really good. Subarus are very difficult to get all the air out.

[Bingo6104]

Originally Posted by bstone

Make sure you burp the radiator really good. Subarus are very difficult to get all the air out.

Whats the best way? i have taken the vent screw out,, started the engine and filled and filled till it wouldn't take any more...I tried to drive it 10 miles and was in hopes in it making it to let it cool down to recheck but it over heated and spewed out the over flow..

When i done the stock thermo change yesterday evening i even had the front end up in the air as best as i could while i was filling it up.

Coolant is getting expensive lol i think about $40 in coolant alone in the past few days..

[bstone]

My preferred method is thus: I pour in the coolant and then squeeze the upper and lower radiator hoses. This makes the coolant go up and down and displace water deep in the system. I keep squeezing the hoses over and over and keep topping it off. I do this until the coolant doesn't drop any further, top it off and cap it.

Despite all of this, I think your HGs may be bad. I would get a chemical tester kit from Advance Auto Parts or AutoZone and check for hydrocarbons in the coolant.

[Bingo6104]

Originally Posted by bstone

My preferred method is thus: I pour in the coolant and then squeeze the upper and lower radiator hoses. This makes the coolant go up and down and displace water deep in the system. I keep squeezing the hoses over and over and keep topping it off. I do this until the coolant doesn't drop any further, top it off and cap it.

Despite all of this, I think your HGs may be bad. I would get a chemical tester kit from Advance Auto Parts or AutoZone and check for hydrocarbons in the coolant.

Ok i will try this to make sure... Those tests, any idea how much? I tried searching on the sites for chemical tester,and hydrocarbon and no results are found...

[bstone]

Originally Posted by Bingo6104

Ok i will try this to make sure... Those tests, any idea how much? I tried searching on the sites for chemical tester,and hydrocarbon and no results are found...

You can rent them at either of those stores.

This is a video on how to use the test:

How To Tell If Your Head Gasket Is Blown - YouTube

How To Tell If Your Head Gasket Is Blown - YouTube