"Normal" overheating?

[Nomake Wan]

Today I went on a bit of a road trip to inland California where the temperatures are quite a bit higher than where I live. I was cruising along at about 75 when I noticed that the A/C wasn't blowing cold. My first thought was it lost charge, but then I remembered back on the road trip when we passed through Needles, CA the A/C shut off to save the engine.

Sure enough, my temp gauge was at about 75% high. Yikes. I backed off the throttle and cruised around 55 (much to the dismay of other drivers) to let the engine cool down.

After more driving and testing, I found that if the outside temperature is indicated as above 94 F, going above 2250 RPM causes the engine to gradually heat up past 50%. After 50% the A/C shuts off. If above 3000 RPMs the engine heats up more quickly, to where it was when I first noticed the problem.

At one point, outside temperature was indicated as 97. Not the highest I've seen (Needles was like 108 or so) but quite high. However, it perplexed me that Evos and RX-8s were going by like nothing was wrong. And didn't they drive the SVX through a desert? Isn't it supposed to be able to handle this sort of heat?

I did replace the radiator a while back. Along with it, the thermostat and water temperature sensor were replaced. Now, I did the water temp sensor myself... but my mechanic actually installed the radiator and supposedly replaced the thermostat. So I can't be positive how it was done.

Is this normal? Other cars seem to have little trouble doing 70+ in that heat... I'm wondering if there's something wrong with my cooling system, or at the very least something I could check...

Thanks for going along with my silliness.

[ensteele]

i have had my different SVXs going over that many RPMs and in that high heat without any problems. I don't know what the problem is, but it does not sound normal.

[nexus_7]

When it is supper hot here in chicago 100+ I dont have those issues. I would pull the radiator out and make sure it is clean, when I just did that with mine I found the bottom 3-4 inches was clogged with leaves and assorted other junk.

Just one mans idea.

Greg

[NiftySVX]

Sounds to me like a restricted or clogged radiator to me too. The car should be able to maintain temperature up to about 120 degrees or so, even higher if moving.

[Nomake Wan]

Thanks guys, will see if that's the case.

[kwren]

could be one of the 2 fan motors are not running to cool the radiator. if it heats up you could just stop and look to see if they are both running. They are supposed to be when the temp gets high. also that would make the air conditioner shut off because the high pressure side pressure will cut the compressor off when the pressure gets too high. Good luck.

[dcarrb]

Originally Posted by Nomake Wan

Is this normal?

Definitely not. My temp gauge actually reads a tick lower with the AC running, I figure because the cooling fans are doing their thing in earnest. August was blistering here, with many days in the high 90s to 100+, and I've had no problems. Stopped in traffic or at a drive-thru, I do keep one eye on that temp gauge.

I don't recall ever observing only one cooling fan running on my cars.

Before you go pulling the raidator, start by being sure the cooling system is properly filled. Top-off the radiator when cold, then fill the overflow reservoir. If the car still overheats you can probably rule-out low coolant as the cause. More likely, you're losing coolant due to overheating, not the other way around.

dcb

[Hocrest]

Originally Posted by dcarrb

I don't recall ever observing only one cooling fan running on my cars.

You're correct.
If working properly, both fans come on together. But they are 3-speed. Depending on Engine temp, AC, Vehicle Speed and other factors, the ECU runs them slow, med or fast.

If a car is overheating while moving it will not be because of the fans. Any consistent speed will move more air through the radiator than the fans can on their own.

[kwren]

Originally Posted by Hocrest

You're correct.
If working properly, both fans come on together. But they are 3-speed. Depending on Engine temp, AC, Vehicle Speed and other factors, the ECU runs them slow, med or fast.

If a car is overheating while moving it will not be because of the fans. Any consistent speed will move more air through the radiator than the fans can on their own.

been there done that!
We have verry little air flow through our radiators and when one of my fans stoped working the car over heated on the freeway. Turn ac off and temp went down a bit

[Nomake Wan]

Just took it over to Garage Tuning, a local Subaru-specialist tuner shop. Great guys, met them at a meet in San Diego. They took a look at it and don't think it's head gasket, and if it is then it's incredibly minor because the radiator isn't leaking (and is full) and the resevoir is also full still. Considering how many Subaru engines they had sitting around the shop, I'm inclined to go with that. He said watch it over the next month. If in a month there's no change, don't worry about it. It's due for a 90k mile service in 3k miles anyway.

So the verdict is... keep driving it, keep an eye on it.

Now to worry about the rest of the car... *rubs hands together*

[SSSVX]

good to hear is a better news.