95 Legacy Runs warm (sometimes) HG?

[gmorell]

Here is the situation. I've had this car for a couple months now. It's got 210k with the 2.2l non turbo, manual. Car runs very smooth and was taken care of by somebody.

 

When I first got it, I drove it out to drop off my kids and it's about a 40 mile trip one way. Drove there and about half way back the temp gauge starts to climb. Never gets above 3/4 of the way to the H. I pull off to check it out and the overflow is boiling over. Both fans are on. I let it sit for a little bit and filled the water back up in the radiator. Drive home and it was fine the rest of the way. I decided to check the thermostat and boil it. Sure enough it's bad. Replace it and go about my day. This is the only time it has run hot under a load.

 

A few days later I'm driving along on the freeway just fine. I exit and while sitting at the light, the temp starts to climb again. I get home and same thing where the overflow tank is running over again. I notice that the gasket on the rad cap is bad, and replace it. All is well again.

 

A few more days out, I develop a leak in the nylon bleeder screw on the radiator tank. I replace it and hope that's that.

 

A few more days, it does the same thing with exiting the freeway. I go home and notice that there isn't a clamp to hold the overflow line onto the radiator, so I put a clamp on it. Hoping that's it.

 

Yet a few more days, it does the freeway exiting thing again. I get home and notice that the upper rad hose looks to be deformed and sucking shut. So, I think, "I've got this nailed, finally". Not.

 

Today, I take it out to go to the airport, about a 20 min drive. This is where it gets interesting. I drive about half way there and get caught up in traffic. It starts to get warm again, never more then 3/4 of the way up the gauge, otherwise I would have killed it. As the traffic starts to break up, It starts to cool back down to normal. Traveling some more, we hit more traffic and it does the same thing. Now, when I finally make it to my exit, it's fine, back at norm temp. about 1/4 of the way up. I drive around the airport for about 20 min and it's just fine. I decide that I'm going to take surface streets back and take the freeway for the last few miles. It's fine all the way back home. I did 60-65 on the freeway for like 9 miles got off the freeway and drove the 2 miles home, and it's just fine. When I got home I decided to check the water level. The overflow is right where it was when I left and the rad it still full. However, both fans are running and the coolant is cold to the touch. (I put my finger in the tank). My laser reads about 70F on the rad. The top hose about 116F. Now here's where I get confused. The top rad hose when I first squeezed it was full. A few min later it was empty, I made a 10min phone call (the car was running since I pulled in the driveway, never killed it and it never got past normal temp.) The hose is full again. So, I shut the car off and start it back up, the fans stop and all is well again. I should add that I had heat the whole trip, it's freezing here. I did hear some bubble in the heater core once or twice.

 

So, the only thing I can think of to explain this is that I had a big air bubble that burped and that's why the hose was empty and then full. I haven't driven it again to see if the problem still exists. However, after all this I am not that confident. As far as the fans running, I have not a clue why they shut off after an ignition cycle. I'm also thinking that the rad might be clogged up. When I ran some water through it, there was a bunch of crap that washed out.

 

I read on some thread that this is a sigh the HG is going out. I've looked for all the tell tail signs and I've got no smells out the exhaust, nothing in the oil or water. No junk or debris in the water or overflow. I'm not bubbling at the overflow either. The engine runs very smooth and has plenty of power too.

 

Sorry for the long post. I wanted to get everything I knew about the problem up for consideration.

 

I should also mention that when it does start to overheat that raising the RPMs to about 1200-1500 cools it right back to normal.

 

Thanks for all your help.

[johnegg]

there is a similar thread on another forum and his was the water pump. when he removed the timing belt he found play in the WP shaft.

 

it sounds like at speed you have enough cooling but at a stop after driving hard, you don't. that could be a clog or a bad pump. i would think bad gaskets would over heat at speed, and give you bubbles in the overflow.

 

but before i pulled the pump i would

install a subaru t-stat, if you compare after market to a subaru oe you'll see why.

flush the entire cooling system, maybe back flush the heater core,

fill and burp the system.

and try it a few days, or until it over heats.

 

fill the rad slowly with thew vent plug open. start the car with the cap and vent open and let it idle until it reaches full operating temp and the t-stat opens. top off the coolant and put on the cap. this should not be done with the front of the car pointing down hill, level or up hill is better.

[gmorell]

It has a new Subaru T-stat. I think I'm going to try burping it again and see what happens.