1979 Pontiac Trans Am

Engine Cooling problem
1979 Pontiac Trans Am V8 Two Wheel Drive Automatic

First I would like to understand why it is my radiator periodically pumps fluid from the release valve. My father had apparently mistakenly filled it the other day with the garden hose to make sure it was alright and ever since it has periodically pumped out a lot of fluid. From what I have read it is normal if it has been over filled but it has been pumping out a lot of fluid. Second I can't properly hook up my water pressure gauge. The water pressure gauge on my dad's car is hooked to a switch on the intake manifold which mine doesn't have. Instead I was told to look between the #1 and #3 spark plugs and all I have found is a large threaded bolt with a square hole at the end of it.
May 13, 2010.

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