Radiator overflowing from overflow resevoir.

[Azplinker]

Thanks for all the help and guidance. Trying to understand what is happening with this vehicle. Timing is good: 8-10 * advance. Runs fine as far s I can tell. A little underpowered , but without another one to test with it's hard to tell if there is really a problem. No bubbles in RAD, No oil in AF. No AF in oil or transmission fluid either. Idle seems to work correctly. 1200 rpms until it warms up, then down to 800 after that. Temps steady and doesn't overheat sitting at idle or on the road. Haven't tried pulling a long hill though. Wondering now if I overfilled AF because I forgot that not all AF in engine will drain from petcock. Think I got about 1/2 gallon or so when I drained it. Book says 10.7 Pints for capacity with automatic. That's about 1 and 1/4 gal. Hard to measure when it won't all drain out. Should the fluid always be at the top of the radiator or just watch the level in the overflow resevoir? Maybe the thermostat is a little slow to open and the RAD cap was bad without a vacuum seal[/size]. Have to wait for more time to pass as this is 19 yr old son's car and he doesn't drive it very far most of the time. I'm watching the AF in the overflow resevoir after sealing the RAD cap back on and will try to decide if I need to do the compression check or change the thermostat.