So here's the deal. 85 GL auto EA82. Drives great and runs great. When kept under 4k rpms runs normal temps. You can drive 55-60 for 8 hours and no problems. But if you are I-25 cruising 70, it starts running hot (pass the middle by not in the red, but almost). This is even when blasting the heater. It has never when into the red but I have drove it for hours with it close to the red because I had to.

 

It's doesn't leak a drop of anything? I had a complete tune up this year; plugs, wires, cap, timing belt, everything. The only thing that is not stock has been the weber I put on last year. Replacing the themo tomorrow, but what else could I check while I screwing with it tomorrow? This needs to get fixed because I don't what to crack a head or screw something major... I love my subie!

 

Thanks in advance!

 

PS- coolant and oil levels normal... ?

Edited October 31, 201114 yr by GLwagonlove
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if it's that consistent the radiator is partially clogged or possibly the water pump impeller is aged.

 

radiatorbarn.com you can often get new radiators for well under $100 shipped to your door.

Have you replaced the water pump. I would suggest either the water pump is inefficient due to corrosion, or the radiator is corroded/clogged.

 

your symptoms sound like inefficient cooling system more than say, a bad HG.

 

But the HG can be compromised if it is overheated too much.

Do thermostat first, then radiator. Thats been my story on all mine at least. Usually its the radiator.

Make sure and get a therostat from the dealer. Waaaay better than the auto store crap.

Make sure and get a therostat from the dealer. Waaaay better than the auto store crap.

+1, might as well do it right if you're going to drain antifreeze and go through the trouble.

Thanks everyone. I will try the themo and then the rad. I'll let you now how it turns out.

Overheating with higher speed is a classic symptom of an inefficient radiator. Not a difficult fix for a home mechanic. And yes, do the thermostat (OEM) at the same time. It's not likely to be the thermostat since a clogged one would definitely cause you to overheat; and if it stayed open all the time, you still wouldn't overheat. It's the radiator.

 

And avoid a suggestion to backflush the radiator. That's never helped and costs almost 40% of cost of a new radiator.

Ok, thanks. Will do!

Well I flushed the rad and did the themo. Ran it up to Dacono from Fort Collins on I-25 and everything seems to be fine. It never even got to the half way point, more like just a quarter.

 

Thank goodness...

 

I hope the subie keeps kicking it for many miles to come! Thanks guys for the all the great input as usual!

Sweet. Don't you just love an easy fix? They are rare!