I drained the system and flushed twice. Then filled through the expansion bottle.
50/50 distilled water and zerex G05.
I did not fill the head before starting. A true senior moment!

Now: Everything goes well at first. Temp guage sitting at just below 9oclock.
Then after a long hot run, on a hot day with a/c on, temp guage rises just above 9oclock, and eventually about half way between 9oclock and red.
Once I turn the ac off, it takes a while but the guage will return to just above 9oclock.
Compensation board has been bypassed.

I havent noticed any steam from the tail pipe, or any goo under the oil filler cap.

Any suggestions.

Thanx

LS.

For the most

Is the Overflow bottle half filled now?

When the car reaches temperature, is the Upper Radiator hose HOT? If not, you may have to Burp the system.
Get engine to Prper Temp, garb the upper hose and squeese it hard and fast about ten times. The hose should get real hot as Coolant starts to circulate properly
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm

Thanks for your response.
I did the burp thing. Squeezed the upper hoses and all.
Right now Im thinking it may be the radiator. Because the temp stays right on the mark until I turn the ac on, then once the heat builds up its hard to get rid of it. If I turn the heater on full, the temp immediately drops down below the normal mark. Im thinking maybe the radiator is not keeping up. It is the original rad.(174000mi)

This all started after I flushed using prestone cooling system flush.
Im thinking a new radiator(possibly a 3 row) would eliminate this problem.
Id appreciate any comments you might have. All comments and advice welcomed.

Thanks

Lawrence

I replaced my original radiator after 200K miles. You might want to take a garden hose and blast through the radiator from the engine compartment outward. I do this every time I replace the Timing Belt The Fan is out of the way to make it easier You will be surprised how much crap gets stuck in the fins of the radiator. It might be enough to not keep up with the AC..
I couldn't hurt to try it.
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm

Thanks
I took the water hose to the radiator yesterday afternoon. You're right, I had no idea so many bugs etc were trapped in there. Now all I need is another hot day to see how things go.
If I still have a problem Im looking at the alum/plastic 3 row nissen radiator from autohauz $153.00 (autohauz.com). Any comments on that.

Thanks

Lawrence

I went with the Nissen equiv to stock. I think it was the 2 row.

Do a Search on Nissen Radiators...many people here have opinons on these 3 rows. I think I remember Closeness to the Fan being in someones comment
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'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm

I cant find any markings on it. The tanks are metal.
Ive had the car since aug 00,but no maintenace records prior to that date.
It is definetly the same radiator I bought the car with 8 years ago.

maybe I'll just have it rebuilt.

Thanks again

Lawrence