I have a 90 Legacy, 2.2L engine, 5 speed manual, and this problem...

 

I pulled into my driveway a few days ago and was greeted by a great deal of steam coming from the radiator, as a well as a coolant leak coming from the passenger side of the radiator (hard to say exactly where... I'll get to that in a minute).

 

Topped off the remaining coolant with water after letting it cool down for a few hours, and nothing leaked out. Ran it again. After about 10 minutes at idle, occasionally gunning the engine, I again notice the leak from the passenger side, accompanied by a little steam, as one would expect. I could also hear boiling in the upper passenger side of the radiator and the upper radiator hose.

 

So I'm pretty sure I have a smallish leak in the radiator that only shows itself under pressure. I've yanked the thermostat, and it seems to functioning, though I'm not sure I'd know a bad stat if it hit in me in the face. Cheap to replace at any rate. Hoses seem fine, they weren't source of the leak.

 

So I need to replace the radiator, but I have doubts that this was original cause of the overheat. I was leaning toward the thermostat, but this one seems to be functioning (opens up at about the right temp).

 

Any ideas/suggestions?

 

Also, how likely is it that I've blown the HG? I've had rather bad experiences with overheating aluminum heads before.... No readily visible signs of oil in the coolant or vice versa... any simple tests I can do on my own to find out?

 

Thanks in advance,

 

Chris

Sounds like your radiator does have a leak so just replace it. Might as well do both hoses and stat while you are at it. Subarus are not nice when they get air in the cooling system, that might be why you hear the bubbling...air pocket. Check the board to see how to propery "burp" the system after the install of new parts.

 

Good luck.

 

I used a Handi-vac to burp my 90 legacy

Search "coolant replacement", or just know that you must detach the upper rad hose and fill as much as possible through here to begin with, before filling the rad.

 

Get a new thermostat gasket too.

Thanks guys, I'll check out those previous posts.

 

Some (probably) important info I left out due to the late hour (never post past your bedtime). The car has around 170K on it. The hoses look like they've been replaced, but other than that, its probably all the original parts I'm dealing with here.

You might want to check and see if you have a plastic radiator. My 90 legacy's original radiator had plastic side pieces and the passenger side cracked at about 170k. I had to replace the entire radiator - this time with a full metal one. Good luck. Dave

You might want to check and see if you have a plastic radiator. My 90 legacy's original radiator had plastic side pieces and the passenger side cracked at about 170k. I had to replace the entire radiator - this time with a full metal one. Good luck. Dave

exactly, it's actually very, very common in all vehicles (even trucks) the sides are plastic and once cracked...you're f*d. I just replaced mine for $120....it's cheap and a pretty easy swap out.

 

once it warms up use a flashlight and shine it on the passenger side, you probably have what looks like a hairline crack but you'll probably actually see small, sharp jets of water shoot out of it.

Also, how likely is it that I've blown the HG? I've had rather bad experiences with overheating aluminum heads before.... No readily visible signs of oil in the coolant or vice versa... any simple tests I can do on my own to find out?

Good advise on all other responses.

Very little chance you have a bad HG the 2.2 is one of the best motors Subaru has every made.

Thanks for all the background info. Good, in a way, to know that these are fairly common problems.

 

Good, also, that this forum exists. You guys rock... but you already know that. ;-)

 

One of my previous autos was a 88 Isuzu Trooper, which due to a belt failure overheated (not nearly as dramatically as the subaru), and within the space of about 5 minutes (about how long it ran overheated) it blew the HG... turned the contents of the radiator into something resembling a chocolate milkshake. This is the my previous experience with overheats, so I've been rather pessimistic about the state of the subaru engine after this overheat, as I probably ran it about that long in an overheated state.

 

Interesting that you say this is one of the best engines Subaru has ever made. This car is something of a hand-me-down, and I know little about it. Its good little perfomer for the size, I take its rugged as well then?

 

Thanks again, you guys have been a huge help. Next time anyone of you is in Bozeman, look me up, I'll buy you a beer.

Interesting that you say this is one of the best engines Subaru has ever made. This car is something of a hand-me-down, and I know little about it. Its good little perfomer for the size, I take its rugged as well then?

 

Yes very durable motor, good performance, good life, etc.

I will take you up on the beer if I ever am out that way!!

Ok... an update, and a few more questions.

 

I've replaced the radiator and the thermostat, which has taken care of the leak, and (for now) the overheating. I haven't given it a good run on the highway yet, but at least it isn't overheating while sitting on the driveway idling.

 

By the amount of coolant I've added, I'd say that I still have air in the system. I've read a few posts concerning the proper bleeding of the system, but I'm still a bit confused as to the exact procedure. Do you run the engine with the bleeder cap off, adding fluid as necessary.... or run it, then bleed it and add fluid while its off?

Fill to the neck. Cap off, start the engine. If the level rises immediately, shut off the engine. A bubble will probably burp out. Start the engine again. Cabin heat on full, blower motor on low, and the engine should be able to reach near operating temperature before coolant spills over. As the coolant level rises again. Put the cap on! Take the car for a short drive - eyes on temp gauge - and park it on level ground. Let it cool, for at least four hours. Check level and top off if necessary.