Okay, I've just most things on this friends EA ... Im trying to get it sorted out for her because she's pregant and about to pop within the next week, and needs to drive her EA to brisbane from the sunshine coast and back .

Okay, here is the problems.

Driving around town, Even on hot days, Not a problem, does not over heat.

Only when, After about 30mins of hwy driving, The temp goes up ... to overheating .

There is no leaks into the motor, And it does not lose any water .

I flushed the radiator that was in there, flushed the total system with the heater on, Hoped that would fix. No luck

Replaced the radiator, flushed everything again ... Still no luck

Replaced the clutch fan, once again, still no luck .

Blew all the crap out of the A/C condensor at the front, to clean more air way, Still no good.

It does not have any head/cracks/gasket leaks, oil is still nice, and does not loose any water at all .

Its not the guage, replaced that .

Only other think I am thinking, Is that, Could the water pump be buggered? ... If so, would it not overheat all the time? .. and mostly around town in stop start traffic? .. Because it stays nice and cool then .
Just only on the hwy, It over heats, when sitting on 100kph for about 30mins .

My other thought where, Something could be blocked in the heater core? ... Or heater pipes? ... Maybe water is not flowing though enough? ..

Could it be that there is a water jack in the head thats blocked? ..

But don't really wanna pull the head off, when it does not have any cracked gaskets or head ..

Got me wondering what else it would be? ..

Its just a stocko 88 EA GL auto ..

Any advise would be great ..

cheers.
Antony.

Check your Thermostat, make sure its the right one, or go for a colder one. I think standard for a EA was 92deg you could try a 88deg, but don't go to low or the ECU will run the mixture richer.

You say you replaced the radiator, was that with a new radiator or a second hand one?

I doubt its your water pump.

Yeah, replaced the thermostat, I used a second hand radiator with one that I here that I was running in a EA before I wrecked it, Never had any over heating problems with that radiator ...

Yeah, Did not think it was the water pump .

I had lots of cooling problems with my old EA, a mate who work at a radiator place told me the radiators were prone to blocking up with casting dust. In six years I owned it he had cleaned out the radiator twice and replaced it twice.

It might be worth taking it out and having it professional cleaned. I costs about $90 with new seals

im an apprentice mechanic and we see this problem abit. Get the radiator professionally cleaned, a flusch wont do it. We had one last week 75% blocked, was only overheating on highways. Have professionally done.

James