2002 Outback, running hot!

[jseabolt]

Long story but today my wife and I had to take possession of her son's 2002 (or 2003) Outback from an impound lot today about 20 miles from our house. I'm trying to talk her into not letting her son have the car back since her name is still on the title. Let's just say he has "issues" he needs to sort out.

 

It's has the H-6 engine and a whopping 280,000 miles on it. Technically the car is totaled due to it's age and mileage. I'll need a front bumper, driver's side fender, rear driver's side door but it runs. 

 

I drove the car home and noticed numerous issues. Most of which I can fix myself (popping CV joint, stuck rear brake caliper, metal to metal, low brake pedal (probably low on brake fluid because the brake light is on) but does have brakes, just not good brakes.

 

It was around 90F today. I tried to get the A/C to work but it has this funky automatic climate control totally unlike the cabin controls on my Baja. My Baja has three knobs. I could barely read the digital readout and what mode it was in so I just turned it off.

 

All seemed fine while driving at 55 mph on the main highway. I do know at one time I glanced over at the temperature gauge and it was in the middle just like my Baja.

 

I got about halfway home and was sweating to death so I decided to see if I could get the A/C to work while waiting at a red light. 

 

I started messing with the climate controls and eventually it started blowing ice cold air out the floor vents then further meddling got it to blow out the dash vents, then the temperature from the vetns started to fluctuate for some reason, perhaps low on refrigerant causing the low pressure switch to kick the compressor off and on. But that's another issue...

 

While pulling away from the red light I noticed the temperature guage was about 3/4 of the way. So I turned the A/C off.

 

Eventually the temperature guage started to drop but was still a bit higher than what I've seen my Baja run at. When I got on the main road (30 mph) it started to run hotter, almost in the red.

 

When I got home, I popped the hood.

 

Both fans were running.

 

The coolant in the overflow tank was boiling so it's not low on coolant. Not to say that the coolant may be old or the wrong ratio. I did notice the outside of the overflow tank had a rusty muddy residue like it had overflowed once before.

 

A blown head gasket is the worst case scenario. But no oil mixing in the antifreeze and no antifreeze in the oil. I did not notice any steam coming from the exhaust. Those are three tell tale signs I know , of, of a blown head gasket. Also no surging, car runs smooth overwise. My Fiat Spider blew a head gasket and was dumping antifreeze into one of the cylinders and it would almost throw me into the dash at times.

 

I have seen bad radiator caps on my Fiat Spider cause the engine to run hot and coolant to boil over out the overflow tank.

 

My guess is the radiator is clogged and may need to be flushed out. This would explain why when I turned the A/C on, the hot gas in the condenser added to the problem.

 

Could be a bad thermostat but the engine did not seem to overheat initially. Also the faster I drive, the cooler it seems to run.

 

How can I rule out the notorious Subaru blown head gasket?

 

My bets are the cooling system needs an enema and possibly a new radiator cap which be a good start.

 

One last question. I'm going to try to back flush the cooling system and run some Prestone flush in it. Which heater hose do I need to install a flush tee in? The one on the driver's side or passenger side?

 

Thanks guys!

 

 

 

[DaveT]

"A blown head gasket is the worst case scenario. But no oil mixing in the
antifreeze and no antifreeze in the oil. I did not notice any steam
coming from the exhaust. Those are three tell tale signs I know , of, of
a blown head gasket."

 

This is not typical of Subaru headgasket failures, except for *very* well blown ones.

 

What you describe is a typical failing headgasket.   Typically, if the coolant gets low for *any* reason, and the engine runs above normal operating temperature [not necessarily in the red] the headgaskets will be damaged.  You may be able to run for a while longer, if you keep the coolant full, refilling before every drive, but it will get worse as time goes by, and worse quicker every time it runs above normal.

 

How to verify damaged headgaskets:

fill radiator.  fill overflow tank to line.

Short drive / run.

 

When cold, squeeze the upper radiator hose sharply, listing for gurgles and the giggle pin.  Remember the sounds.

Check the level in the tank, add if low.

Drive, but no farther than safe return w/o over temp.

 

Repeat this at least a few times.

 

If there are no leaks, there should be less air gurgling each time you check the upper hose, and coolant will be drawn into the system from the tank.

 

If this is not happening, there is either a leak loosing coolant, or the beginning of headgasket failure.

 

When the failure gets bad enough, there will be a steady stream of bubbles in the overflow tank.  This check is after the engine achieves normal temp.  As it gets worse, it will begin to push the coolant out as well, causing overflow of the tank. 

 

I had one over normal temp experience, where the fans didn't run -[ I had forgotten to reconnect them after a timing belt replacement] -  the system was full.  It survived with no ill effects.  No bubbling was involved.  Plugged the fans in, all was well.

 

 

 

 

[Fairtax4me]

Head gaskets blown.

 

Leakdown test is the best way to confirm it. But the boiling in the reservoir is the biggest giveaway.

[golucky66]

I'm going to give my two cents here. I bought a 2000 Outback which everyone thought had a blown HG, so i got it for a STEAL. Anyways, same hing, driving faster would make it better, and it would crawl up if your idling or driving less then 45. After doing some tests I couldn't get any true signs of a HG failure besides "it's overheating".

Turns out I had a bad radiator and the faster I drove the easier it was for the bad radiator to cool the engine.

 

While I will admit subarus have issues with HG's a lot. A lot of people are really quick to diagnose almost any overheating issue as a bad HG. 

I would definitely realize it could be a bad HG, but why dive right into a $2000 bill when it could be a $400 radiator. Get a proper diagnose from a shop that understands subarus and let them tell you if it needs a HG. 

Edited August 7, 2016 by golucky66

[DaveT]

This is why I include a description of how to verify, rather than outright guess. Often, the first description doesn't have enough information. I also usually add how to avoid making the problem worse, so the diagnosis can be made without causing bigger problems.

[golucky66]

This is why I include a description of how to verify, rather than outright guess. Often, the first description doesn't have enough information. I also usually add how to avoid making the problem worse, so the diagnosis can be made without causing bigger problems.

Wasn't trying to insult, just being clear to jseabolt that it may not be a HG. And that a proper diag should be done before any assumptions are made

[idosubaru]

Was it wrecked? You mention damage and totaled?

 

Headgaskets are most likely but rule out other things first:

Low on coolant/needs burped

Clogged radiator

Thermostat ( highly unlikely, not bestie as common as they're mentioned.)

 

Previous poster - how long ago did you replace radiator and did you confirm it was bad with a flow test or another test?

 

Sometmes people repair a subaru overheating and the issue comes back later - it just seemed like it fixed it.

[golucky66]

I replaced the radiator right after I bought that car because about 1/3 of the fins were missing (it didn't leak a drop of coolant out of the radiator). Didn't flow test it before replacement. Once the old one was out, I stuck a garden hose in the upper port and didn't get much flow out of the other end. So that in combination with the fins missing caused that overheating concern. Drove it with that new radiator for 2 years before I sold the care because I got a good deal on an impreza. 

[jseabolt]

Once again sorry for the late reply. 

 

I ASSumED because coolant was boiling in the overflow tank, it had coolant in it.

 

Well the next day I popped the radiator cap and so no coolant. So I topped it off with my 50/50 mix. I think I added about a 3 liters! I think the capacity is around 6 liters?

 

Started the engine and allowed it to get to normal operating temperature. Eventually the fan kick on. Then turned on the air conditioner and let it idle for about 10 minutes. Both fans kick on and needle stays in the center.

 

Also added quite a bit of brake fluid but the pedal still goes to the floor but does stop (poorly). So I guess the bad brake caliper has sucked what fluid was in the reservoir out and now air has got into the braking system.

 

I did not drive the car on the road due to the poor brakes and my step has no insurance on this vehicle (illegal in TN).