Overheating Subaru Legacy AWD Wagon...

[Hachiroku $B%O%A%m%/(B]

1997 Subaru AWD wagon, "L" model, basic car. Replaced coolant and
thermostat and ran car static for an hour at a time about 3 times. Would
initially overheat (when I replaced the coolant), cold air coming from the
heater, then heat started coming from the vents and the guage went down.
As I was getting it ready to pass inspection I would run it for 40-60
minutes, temp guage rock-steady at half way, heat from the vents, etc.

On the first drive yesterday, I got about 8 miles and it began
overheating, after running static for about 40 mins with no problems. I
shut it down and let it cool and drove it home. Sometimes raising the revs
causes the temp to decrease, and sometimes to increase. Sometimes coasting
cools the car off, and sometimes raises the temp. Putting it in neutral
has no effect; it keeps getting warmer.

When I opened the bleeder screw, pure steam was coming out of it. From the
front of the car, the right side (driver's side) appears to have coolant
in the lower radiator hose where the thermostat is, and the upper hose
looks empty.

I don't know what size the engine is. It came from the factory with a 2.2,
but it has been replaced, with another 2.2? I was told the trans had been
replaced with a FWD trans, but the sticker on the trans matches the VIN
plate, which indicates AWD. Trans works great, car runs well, except for
the overheating. I replaced the t-stat, and the one that was in there
looked new also. I'll have it flushed sometime this week.

Anyone seen this before, or have any idea what's going on here? It looks
like a blockage somewhere.

 

[Jeff]

1997 Subaru AWD wagon, "L" model, basic car. Replaced coolant and
thermostat and ran car static for an hour at a time about 3 times. Would
initially overheat (when I replaced the coolant), cold air coming from the
heater, then heat started coming from the vents and the guage went down.
As I was getting it ready to pass inspection I would run it for 40-60
minutes, temp guage rock-steady at half way, heat from the vents, etc.

On the first drive yesterday, I got about 8 miles and it began
overheating, after running static for about 40 mins with no problems. I
shut it down and let it cool and drove it home. Sometimes raising the revs
causes the temp to decrease, and sometimes to increase. Sometimes coasting
cools the car off, and sometimes raises the temp. Putting it in neutral
has no effect; it keeps getting warmer.

When I opened the bleeder screw, pure steam was coming out of it. From the
front of the car, the right side (driver's side) appears to have coolant
in the lower radiator hose where the thermostat is, and the upper hose
looks empty.

I don't know what size the engine is. It came from the factory with a 2.2,
but it has been replaced, with another 2.2? I was told the trans had been
replaced with a FWD trans, but the sticker on the trans matches the VIN
plate, which indicates AWD. Trans works great, car runs well, except for
the overheating. I replaced the t-stat, and the one that was in there
looked new also. I'll have it flushed sometime this week.

Anyone seen this before, or have any idea what's going on here? It looks
like a blockage somewhere.

Probably what is happening is that there is air in the cooling system,
resulting in intermittent blockages. you need to bleed the air out.

jeff

 

[Hachiroku $B%O%A%m%/(B]

Probably what is happening is that there is air in the cooling system,
resulting in intermittent blockages. you need to bleed the air out.

jeff

Ya mon, I tried that! When I initially filled the radiator I would make
sure it was full, then open it and let the air out, and then close it,
making sure the bottle was full. It was 'drinking' from the overflow
bottle quite nicely before it started overheating. Even while overheating
it was filling the bottle to the top, and then when you shut it off it
would drop the level in the bottle about an inch.

Tried again today, making sure there wasn't any air (or trying to...)

 

[johngdole]

So what's the state of the water pump and head gasket? Is there strong
flow when you pinch the upper hose? Good flow looking into the rad?
Blown head gasket can give you the same symptoms.

 

[Ray O]

1997 Subaru AWD wagon, "L" model, basic car. Replaced coolant and
thermostat and ran car static for an hour at a time about 3 times. Would
initially overheat (when I replaced the coolant), cold air coming from the
heater, then heat started coming from the vents and the guage went down.
As I was getting it ready to pass inspection I would run it for 40-60
minutes, temp guage rock-steady at half way, heat from the vents, etc.

On the first drive yesterday, I got about 8 miles and it began
overheating, after running static for about 40 mins with no problems. I
shut it down and let it cool and drove it home. Sometimes raising the revs
causes the temp to decrease, and sometimes to increase. Sometimes coasting
cools the car off, and sometimes raises the temp. Putting it in neutral
has no effect; it keeps getting warmer.

When I opened the bleeder screw, pure steam was coming out of it. From the
front of the car, the right side (driver's side) appears to have coolant
in the lower radiator hose where the thermostat is, and the upper hose
looks empty.

I don't know what size the engine is. It came from the factory with a 2.2,
but it has been replaced, with another 2.2? I was told the trans had been
replaced with a FWD trans, but the sticker on the trans matches the VIN
plate, which indicates AWD. Trans works great, car runs well, except for
the overheating. I replaced the t-stat, and the one that was in there
looked new also. I'll have it flushed sometime this week.

Anyone seen this before, or have any idea what's going on here? It looks
like a blockage somewhere.

If you can get an exhaust sniffer, check for exhaust gas at the radiator
neck. When you filled the coolant, you did have the heater set to full hot,
right?

 

[Carl 1 Lucky Texan]

If you can get an exhaust sniffer, check for exhaust gas at the radiator
neck. When you filled the coolant, you did have the heater set to full hot,
right?

Good post.
I think he did more things correctly than most. The ONLY other thing to
consider would be filling/burping the system with the front of the car
elevated OR by using some type of vacuum device on the cooling system. I
have also read of someone filling the system through a disconnected
hose? The best may be to fill (heater on max) with the front on ramps or
up a curb/whatever, rad cap off, run till fans come on/t'stat opens,
check the radiator and fill, fill o'flow bottle to a little over the
full line, put rad cap on, allow car to cool (overnight if necessary)
repeat. If you do not repeat, make sure the o'flow is topped up to the
line, drive car and monitor heat and coolant levels. If you still have
problems - headgasket is the only thing left. Phase I 2.5 engines are
notorious for that problem. A swapped engine may not have been 'purged'
and could easily have a HG problem. Sometimes, comparing sparkplugs will
show one that looks different. That cylinder may have coolant in to it
on occasion from the bad HG. Bubbles in the radiator of combustion
gasses is another. That why an exhaust sniffer would also be diagnostic.


Carl

 

[boxing]

maybe pressure test the cooling system.

 

[Ray O]

maybe pressure test the cooling system.

I would worry that pressure testing a 10 year old cooling system might
create leaks in the radiator...

 

[hachiroku]

If you can get an exhaust sniffer, check for exhaust gas at the radiator
neck. When you filled the coolant, you did have the heater set to full hot,
right?

But of course I did!

Well, after I started adding coolant...

I'm afraid...

"I caught the head gasket leaking in my 97 subaru a few years ago, at 96k.
It cost me $650, and they replaced front and rear main seals at the same
time for just the cost of the seals, somewheres around $50-75 each if I
remember correctly. I knew something was wrong- no power, really poor gas
milage, the engine sounded louder than normal, I was constantly topping
off the oil and the car smelled differently overall."

The engine runs really well, but after talking to a few mechanic friends
and a Subaru service manager this begins to look like a BHG. One estimate
is $600. The car has 336,000 miles on it, but runs well, everything works
and minimal rust.

I said if it had a major problem I was going to get rid of it. I think
I'll take it for Mass state inspection and have them look at it. I go
somewhere anal, so they'll tell me if there's anything else. Hey, $29 for
a complete inspection?!

 

[hachiroku]

Good post.
I think he did more things correctly than most. The ONLY other thing to
consider would be filling/burping the system with the front of the car
elevated

<SIGH> It was up on ramps...BHG I'm afraid...

 

[hachiroku]

I would worry that pressure testing a 10 year old cooling system might
create leaks in the radiator...

Engine has been replaced (don't know how many miles...) and radiator is
new...all adding up to BHG...

 

[hachiroku]

So what's the state of the water pump and head gasket? Is there strong
flow when you pinch the upper hose? Good flow looking into the rad?
Blown head gasket can give you the same symptoms.

I think johngdole has hit the nail on the...er...*HEAD*...

 

[hachiroku]

1997 Subaru AWD wagon, "L" model, basic car. Replaced coolant and
thermostat and ran car static for an hour at a time about 3 times. Would
initially overheat (when I replaced the coolant), cold air coming from the
heater, then heat started coming from the vents and the guage went down.
As I was getting it ready to pass inspection I would run it for 40-60
minutes, temp guage rock-steady at half way, heat from the vents, etc.

On the first drive yesterday, I got about 8 miles and it began
overheating, after running static for about 40 mins with no problems. I
shut it down and let it cool and drove it home. Sometimes raising the revs
causes the temp to decrease, and sometimes to increase. Sometimes coasting
cools the car off, and sometimes raises the temp. Putting it in neutral
has no effect; it keeps getting warmer.

When I opened the bleeder screw, pure steam was coming out of it. From the
front of the car, the right side (driver's side) appears to have coolant
in the lower radiator hose where the thermostat is, and the upper hose
looks empty.

I don't know what size the engine is. It came from the factory with a 2.2,
but it has been replaced, with another 2.2? I was told the trans had been
replaced with a FWD trans, but the sticker on the trans matches the VIN
plate, which indicates AWD. Trans works great, car runs well, except for
the overheating. I replaced the t-stat, and the one that was in there
looked new also. I'll have it flushed sometime this week.

Anyone seen this before, or have any idea what's going on here? It looks
like a blockage somewhere.

From another web site:

"Common symptoms:
Overheating, often when slowing or stopped after extended high load
driving. "

Sort of, although it's not random...


"The overheating can be seemingly random and sporadic."


Nah, it's pretty steady!

"Bubbles in coolant overflow reservoir, immediately after running."

Nope...steam in the radiator!

"Sludgy residue in coolant overflow tank."

Hmmmm...the original coolant didn't look good when I drained it out...
it was kinda dark...I thought perhaps there was just gunk in the motor...


"Hydrocarbons in coolant overflow tank, this is tested by a mechanic with
specialized equipment and is not evident visually."


Having this looked at Wednesday...

Is there any way I can check this myself?

 

[Bruce L. Bergman]

But of course I did!
Well, after I started adding coolant...
I'm afraid...

"I caught the head gasket leaking in my 97 subaru a few years ago, at 96k.
It cost me $650, and they replaced front and rear main seals at the same
time for just the cost of the seals, somewheres around $50-75 each if I
remember correctly. I knew something was wrong- no power, really poor gas
milage, the engine sounded louder than normal, I was constantly topping
off the oil and the car smelled differently overall."

The engine runs really well, but after talking to a few mechanic friends
and a Subaru service manager this begins to look like a BHG. One estimate
is $600. The car has 336,000 miles on it, but runs well, everything works
and minimal rust.

I said if it had a major problem I was going to get rid of it. I think
I'll take it for Mass state inspection and have them look at it. I go
somewhere anal, so they'll tell me if there's anything else. Hey, $29 for
a complete inspection?!

Remember, Subaru boxer motor internals are right up there with
Toyotas for being overbuilt to the point of bulletproof, and running
practically forever - If the body and suspension are still good, might
well be worth reworking the head gaskets and just keep driving it.

When it rusts into two pieces, /then/ you can junk it.

--<< Bruce >>--

 

[Ray O]

From another web site:

"Common symptoms:
Overheating, often when slowing or stopped after extended high load
driving. "

Sort of, although it's not random...


"The overheating can be seemingly random and sporadic."


Nah, it's pretty steady!

"Bubbles in coolant overflow reservoir, immediately after running."

Nope...steam in the radiator!

"Sludgy residue in coolant overflow tank."

Hmmmm...the original coolant didn't look good when I drained it out...
it was kinda dark...I thought perhaps there was just gunk in the motor...


"Hydrocarbons in coolant overflow tank, this is tested by a mechanic with
specialized equipment and is not evident visually."


Having this looked at Wednesday...

Is there any way I can check this myself?

If you have an electronic gas sniffer, you can stick the probe into the
radiator neck or overflow tank.

 

[Tony Hwang]

1997 Subaru AWD wagon, "L" model, basic car. Replaced coolant and
thermostat and ran car static for an hour at a time about 3 times. Would
initially overheat (when I replaced the coolant), cold air coming from the
heater, then heat started coming from the vents and the guage went down.
As I was getting it ready to pass inspection I would run it for 40-60
minutes, temp guage rock-steady at half way, heat from the vents, etc.

On the first drive yesterday, I got about 8 miles and it began
overheating, after running static for about 40 mins with no problems. I
shut it down and let it cool and drove it home. Sometimes raising the revs
causes the temp to decrease, and sometimes to increase. Sometimes coasting
cools the car off, and sometimes raises the temp. Putting it in neutral
has no effect; it keeps getting warmer.

When I opened the bleeder screw, pure steam was coming out of it. From the
front of the car, the right side (driver's side) appears to have coolant
in the lower radiator hose where the thermostat is, and the upper hose
looks empty.

I don't know what size the engine is. It came from the factory with a 2.2,
but it has been replaced, with another 2.2? I was told the trans had been
replaced with a FWD trans, but the sticker on the trans matches the VIN
plate, which indicates AWD. Trans works great, car runs well, except for
the overheating. I replaced the t-stat, and the one that was in there
looked new also. I'll have it flushed sometime this week.

Anyone seen this before, or have any idea what's going on here? It looks
like a blockage somewhere.

Hi,
Was it OK before you did the work?
Or you worked on it for overheating problem>

 

[Tony Hwang]

From another web site:

"Common symptoms:
Overheating, often when slowing or stopped after extended high load
driving. "

Sort of, although it's not random...


"The overheating can be seemingly random and sporadic."


Nah, it's pretty steady!

"Bubbles in coolant overflow reservoir, immediately after running."

Nope...steam in the radiator!

"Sludgy residue in coolant overflow tank."

Hmmmm...the original coolant didn't look good when I drained it out...
it was kinda dark...I thought perhaps there was just gunk in the motor...


"Hydrocarbons in coolant overflow tank, this is tested by a mechanic with
specialized equipment and is not evident visually."


Having this looked at Wednesday...

Is there any way I can check this myself?

Hi,
Is the fan running when temp rises?

 

[hachiroku]

If you have an electronic gas sniffer, you can stick the probe into the
radiator neck or overflow tank.
--

Way ahead of you, Ray! Brought it for MA state inspection (remember
those?) He put the gas sniffer for the tailpipe in the filler neck and
there were PLENTY of hydrocarbons coming out through the radiator!!!

 

[hachiroku]

Hi,
Was it OK before you did the work?
Or you worked on it for overheating problem>

I walked into this thing cold, being told it was overheating. After seeing
all the new parts, I knew it wasn't going to be easy. BHG...

 

[hachiroku]

Hi,
Is the fan running when temp rises?

Everything works but the Head Gasket!!!