Overheating Problem... anyone? anyone?

[LedSled]

So... I recently bought my first Subaru, a 91 Legacy Wagon for $500. I knew it would be a bucket but so far i've encountered larger than expected head-aches. The car ran good the first month or so I had it, the previous owner told me it probably needed a new radiator cap (which I replaced when I drove the car home the first time).

However, now, 3 months later, the car is having over-heating issues like crazy. I feel like I've been through everything. I replaced the radiator cap, upper and lower radiator hoses, thermostat, coolant sensor, the radiator itself, the water-pump, bypassed the heater core and yes, it still does it. I'll drive the car, and after about 6 minutes, the needle starts going into the H zone. The car rarely actually "errupts" and spews steam from under the hood (it did once), but the reserve bottle does fill up, and I can sometimes hear the coolant bubble inside the radiator after I've stopped the car and popped the hood to check it out. I've even UV dyed the anti-freeze and searched for leaks. The car doesn't have any leaks, I've left it sitting for a week and came back to the same amount of coolant.

I've checked the oil for any coolant, its just oil. Likewise, I haven't seen any oil in the coolant the numerous times I've drained the radiator. There doesn't seem to be a leak so, I don't think its a head gasket but... what could it be? I do have a bad strut in the back of the car that makes a horrible sound when going over bumps and such, is it possible this bum strut is dragging and causing it?

I'm all out of ideas here. Like I was saying though, it over-heats when I drive (the needle lowers at idle), the type of driving seems to have some effect (going up a hill will push it to the limit a lot quicker). When the heater-core was connected, it constantly blew ice-cold air on every single setting.

Has anyone encountered such a pain the ass before either? I'm going crazy... this "$500 car" has already costed me almost that much in parts alone.

If you can help, thanks!

[canubaru]

it sounds like a bad head gasket. not common in a 2.2L subaru engine, but not unheard of and possible in any high mileage engine.

the repair at a shop could run $1000 - $2000, or much less if you do it your self. other options would be to swap in another engine but it just depends on how much. usually these engines are a good risk , not a lot of problems.

how many miles on the car?

[LedSled]

Thanks for your reply.
Theres 270,000 miles on the car. I thought it might have been a head-gasket too, but it lacks signs of such. The coolant level remains the same (no leak), theres no oil in the coolant, or vise versa, and theres an old trick, with the radiator cap off, turn the engine on, and off and see if the coolant bubbles in the radiator (a sign of exhaust or something escaping). I had no such occurring, so I don't feel like it is the head gasket, Any other ideas?

[canubaru]

well it is possible that the cooling system was not properly ''burped'' after your first overheating / cooling system service / repair. but the 2.2L engine isn't too sensitive to this.

park the car with the front up hill if you can or at the least level, not down hill. fill the radiator slowly, let is sit a while and top it off. start the car and let it run with the radiator cap off until it reaches full operating temp. when the t-stat opens it will belch some coolant and maybe the lavel will drop. top it off again and put the cap on and fill the over flow to the max level. you should be good.


typically these engine will not put coolant in the oil. if the exhaust is leaking into the coolant they will have gunk in the coolant. i would fill the system and drive it until it over heats, the look in the over flow for small bubbles. if it is overheating due to exhaust in the coolant it should show small bubbles in the overflow. the cap will let the high pressure out into the overflow.

who did all the work to the cooling system? a subaru shop?

did you use a subaru t-stat? i'm not sure this would make a difference, but if the t-stat was done first after the cap it may be the issue. some folks insist on a subaru t-stat. i don't think i would replace now even if it isn't subaru until you have tried burping the system first.

so you are not losing coolant? even when it over heats? a hydro carbon test may help, but if the coolant is new it may not show up until it has over heated again.

[Legacy777]

As mentioned, if you didn't burp the cooling system all the way or a non-subaru t-stat was used, either/both could be causing your problems.

Personally, if a non-Subaru t-stat was used, I'd highly recommend replacing it with a Subaru t-stat. I experienced weird temp issues when using a non-Subaru t-stat.....and that was back in 96. Since then, I've only used Subaru t-stats.

Regarding the burping, there is a bleeder screw located at the top passenger side of the radiator. This needs to be removed during filling to ensure all the air has been removed.

I'd start with those two things, and if both are good, it is likely a headgasket issue.

[Danny-G]

Do the fans come one once the temperature gets above normal? If they don't check the under hood fuse and see if its blown.

[beanis05]

it sounds like a bad head gasket. not common in a 2.2L subaru engine, but not unheard of and possible in any high mileage engine.

the repair at a shop could run $1000 - $2000, or much less if you do it your self. other options would be to swap in another engine but it just depends on how much. usually these engines are a good risk , not a lot of problems.

how many miles on the car?

False he said he checked for blow head gasket you are going to stress the guy out

Invest in one of these

this tool will make sure you burped the system all the way. Make sure you read the directions.
This should take care of your problem if not come back and tell us what you have found when trying to burp the system.
Also if the system is burped properly the fans will come on at idle.

[canubaru]

well apparently it's not the radiator, cap, t-stat, hoses, heater core or water pump either. that leaves burping, a blockage in the block, or .... what's left.? fans?

it is hard to imagine that all of this work has been done and it was never properly filled and burped, but if the same guy did it all and didn't how to do it, i guess it could be. i hope it is just burping.

[LedSled]

Just to let everyone know (and anyone in the future who searches this thread with similar problems) It was in-fact, a blown head gasket. I tried burping the radiator like told, but the fluid never dropped, as I seemed to have filled it correctly the first time. It came down to it either being a head-gasket, or having a clog in the block... so I finally took it to a shop to have them figure out the problem, because I didn't want to start such a mammoth project as a head gasket without knowing it was for sure.

The shop diagnosed the problem, however from home, the only indicator was gunk in the resivoir bottle. I will be doing the head-gasket myself (shitty I know...). If anyone has any threads up with pictures on replacing it, please hook me up with a link! In the mean-time i'll be scanning past posts myself.

Thanks anyways fellas.

[asotwavb]

Don't worry man, i felt like i wanted to give up on my legacy GT when the head gaskets went, but after they were replaced the car has been rock solid ever since!

-Good luck

[cul8tr]

I drill 1 or 2 1/8" holes in the t-stat. This allows the trapped air on the motor side of the t-stat a place to escape from. 1 hole if your in a cold climate and 2 if in a warmer climate. I've tried 3 and 4 holes but in winter it will not retain heat while driving.

[Legacy777]

Just an FYI, the stock Subaru thermostat has a "jiggle valve" which allows for air to be purged. Another reason to run a stock Subaru thermostat

LedSled,

Here's info on the heads

http://www.main.experiencetherave.com/s ... Heads1.jpg
http://www.main.experiencetherave.com/s ... Heads2.jpg

Just to let you know, those scans are for the non-turbo engine only. The turbo engine has slightly higher torque specs. You can download the manual in the stuff you need to know forum. I've got a stickied thread with links to the manuals.

[evolutionmovement]

Though I've written it at least a dozen times, these engines seldom display typical signs of blown head gaskets. Primary failure sign is the collection of air bubbles at the water pump impeller, causing cavitation, which the operator sees as seemingly random overheating, particularly under load at a steady state. Perhaps this advice should be a sticky, though I suspect a lot of people don't read them.

[Legacy777]

...though I suspect a lot of people don't read them.

Very true.....

[gijonas]

Typically when "burping" the system, I like to have the car in a position where the nose is at a 45 degree upward angle (ok an exaggeration) but as high as reasonable.Never had a problem when doing it that way.