kimkathan Posted April 12, 2005 Share Posted April 12, 2005 Does anyone have any ideas for a 1990 Legacy SW that has been overheating when it has to "work". Over the past 3 months it has periodically overheated for just a moment, maybe 3 times when going over a mountain or through a snow drift(normal temp, then spikes to overheated, shut off and let it set a minute, then it's fine for another month or so) last week while going through the mud (yes it's mud season here in VT now) it spiked again, this time it didn't go down,. Got out, and the fluid had backflowed into the resevoir tank, but there was still coolant in the radiator. Nursed it home (2 miles), and drove it around the block later (5mi) as long as it's on the pavement it's fine and even in the mud sometimes then all the sudden when you least expect it, it spikes again. We just changed the headgaskets in Sept, and the block at that time came back fine. Put in a new water pump in Jan. changed the thermostat 3 times now thinking that it was sticking, changed the lower radiator hose, as last week when it did it around the house the lower hose was sucked in tight right after it overheated. Flushed the radiator and put in some BARRS seal, Took the thermometer out of the coolant pipe between the heads and changed that, both fans are turning when up to temp. Yesterday we took the thermostat out and ran it to see what it would do, ran it through the mud, up hills for over 20 min. It would go from cool to normal and soemwhere in between but never overheated. We're getting a little miffed at this, have also taken it to a mechanic and he has no idea. Next thing is to change the radiator and then after that is to a Subaru dealer, but they are almost 2 hours away. Heater has been working fine other than when it overheats, or when the thermostat is out. Is there any way of testing to see if it could possibly be the head gasket again? Last time it was REAL apparent, coolant out the exhaust and antifreeze smell, nothing like that at all now. Quote Link to comment Share on other sites More sharing options...
frag Posted April 12, 2005 Share Posted April 12, 2005 Just an opinion, but by your description of the symptoms I would think the radiator is the problem. It barely can keep up and the minute the engine produces extra heat, it's overwelmed. Getting the thermostat out helps the rad a little, but not enough to keep the needle at normal. I think replacing the rad (partly clogged?) will solve the problem. Dont delay cause overheating is bad for the engine block, heads, and head gaskets. Just an idea. Look at the rad fins. Is it possible that 15 years of small rocks flying into the rad has shut part of the air passages where heat is dissipated. My engine is not overheating yet, but i'm going to replace the rad soon before it acts up for that exact reason: about 1/3 of the fins (the bottom part of the rad) have been closed by small debris flying into them. Quote Link to comment Share on other sites More sharing options...
FlyFlicker Posted April 12, 2005 Share Posted April 12, 2005 You may have air trapped in the block. Do a search on how to burp the cooling system and make sure that you get all the air out. Quote Link to comment Share on other sites More sharing options...
blackbart Posted April 12, 2005 Share Posted April 12, 2005 I have a "new" radiator that I bought for my 1990 Legacy three years ago, when I got rid of the car I striped a bunch of parts including the radiator. If you are sure that this is your problem (or if you want a radiator to see if it is the problem) I am asking $50 for it plus shipping from PA 18824. I paid $135 for it. If you need anything else for your 90 let me know, I saved a lot of stuff. Quote Link to comment Share on other sites More sharing options...
ndsnewleg Posted April 12, 2005 Share Posted April 12, 2005 I have a 90 legacy also. I second the radiator burping process as a first step. It's critical to proper functioning of cooling system. The collapsed hose would be an indicator of that problem to me. The haynes manual also has a good description of how to do it. Quote Link to comment Share on other sites More sharing options...
kimkathan Posted April 21, 2005 Author Share Posted April 21, 2005 UPDATE: Still no answers! Replace the radiator, headgaskets, new heads. Still will overheat when worked (no mud now, but will do it going up hills). Had a funnel in the radiator to top off fluids, had some excess water in the funnel (approx 2") When pushing down on the throttle up to around 3000-4000 RPm and holding it there for a while, several very tiny bubbles come up in the water, when the throttle is released, some larger bubbles come up. When the cooling fans come on, the water level goes down quite quickly, but when they go off, the water comes back up in the funnel. Almost wonder if the water pump is malfunctioning. the lower radiator hose does become hot though. Could it be a cracked block? Does anyone know of a way to find out? I have spoken with several mechanics in the area and had a few look at it, their first thoughts were radiator and headgaskets as well, but now are toatlly stupmed as well. Hate to give up on the car, as body is in good shape (solid and minimal rust) and milage is only 160,000. Can't complaine on what I've gotten out of it thought over the past 3 years, just think that it should have many thousand more left in it. Quote Link to comment Share on other sites More sharing options...
Meeky Moose Posted April 21, 2005 Share Posted April 21, 2005 sounds like you have 1 of 3 things, cracked block, headgasket failure, or a cracked head.. Quote Link to comment Share on other sites More sharing options...
bk2 Posted April 21, 2005 Share Posted April 21, 2005 Does anyone have any ideas for a 1990 Legacy SW that has been overheating when it has to "work". Over the past 3 months it has periodically overheated for just a moment, maybe 3 times when going over a mountain or through a snow drift(normal temp, then spikes to overheated, shut off and let it set a minute, then it's fine for another month or so) last week while going through the mud (yes it's mud season here in VT now) it spiked again, this time it didn't go down,. Got out, and the fluid had backflowed into the resevoir tank, but there was still coolant in the radiator. Nursed it home (2 miles), and drove it around the block later (5mi) as long as it's on the pavement it's fine and even in the mud sometimes then all the sudden when you least expect it, it spikes again. We just changed the headgaskets in Sept, and the block at that time came back fine. Put in a new water pump in Jan. changed the thermostat 3 times now thinking that it was sticking, changed the lower radiator hose, as last week when it did it around the house the lower hose was sucked in tight right after it overheated. Flushed the radiator and put in some BARRS seal, Took the thermometer out of the coolant pipe between the heads and changed that, both fans are turning when up to temp. Yesterday we took the thermostat out and ran it to see what it would do, ran it through the mud, up hills for over 20 min. It would go from cool to normal and soemwhere in between but never overheated. We're getting a little miffed at this, have also taken it to a mechanic and he has no idea. Next thing is to change the radiator and then after that is to a Subaru dealer, but they are almost 2 hours away. Heater has been working fine other than when it overheats, or when the thermostat is out. Is there any way of testing to see if it could possibly be the head gasket again? Last time it was REAL apparent, coolant out the exhaust and antifreeze smell, nothing like that at all now. Talk to Northwest..... he seems to know a good bit about this stuff..... read my thread too........it is a good read....you might want to thank me after...) Quote Link to comment Share on other sites More sharing options...
kimkathan Posted April 22, 2005 Author Share Posted April 22, 2005 We have an answer: Was getting to my last hope, herd a sound like a metal band banging around. Decided to look at the water pump....the internal impeller was loose, unlevel and didn't turn easily. Replaced it with another one, seems to be working fine so far for 2 days now. Hopefully things will continue this way. Quote Link to comment Share on other sites More sharing options...
bk2 Posted April 23, 2005 Share Posted April 23, 2005 We have an answer: Was getting to my last hope, herd a sound like a metal band banging around. Decided to look at the water pump....the internal impeller was loose, unlevel and didn't turn easily. Replaced it with another one, seems to be working fine so far for 2 days now. Hopefully things will continue this way. that is the best news I heard today........ keep an eye on her.... Bryan Quote Link to comment Share on other sites More sharing options...
nixon Posted April 23, 2005 Share Posted April 23, 2005 Everyone say DOHHHH, me included. It,s the water pump. Are subie owners born pessimists? Quote Link to comment Share on other sites More sharing options...
sregor13 Posted April 23, 2005 Share Posted April 23, 2005 From the first post all the way through I thought warped heads or cracked block. Glad to hear it was the Water Pump. Your luck is clearly better than mine. Hope it stays that way. If you get the chance maybe you should have the compression checked just to make sure. Thanks Quote Link to comment Share on other sites More sharing options...
bearbalu Posted April 25, 2005 Share Posted April 25, 2005 I read it somewhere - an easy way to check if it waterpump is to turn on the heater when overheat happens. If car cools off, you know it isn't the waterpump - essentially waterpump has enough juice to pump through heater core and isn't the "constraint" in the cooling system. Quote Link to comment Share on other sites More sharing options...
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