1995 Olds Cutlass Supreme engine noise first minute or two

1995 Olds Cutlass Supreme with 126,000 miles. About two weeks ago I replaced the radiator due to a leak. I had to lift/brace the engine a little to get the radiator out since the motor mounts are in the way. After installing the new radiator (water pump, upper radiator hose, and lower radiator hose are also fairly new), I noticed a kind of clicking/coughing/sputtering noise when I start the car for the first time each day (no real effect on engine performance from what I can tell though). The noise last only a few seconds to two minutes until the car warms up. The noise increases as you give it more gas, but as I said eventually disappears, and the car seems to run great the whole day. I also seem to still be losing a little bit of radiator fluid each day, and I find no leaks anywhere (no pooling on the ground at all that I can tell). I've not noticed the radiator fluid looking oily, nor have I noted any foaming/water in the engine oil. I don't notice any water/excess smoke from the exhaust. Any ideas. Could this be a head gasket problem? Could the lifting the engine have caused this (why would this happen all of a sudden)?
I'm not losing oil, or any other fluids that I know of either. I do seem to lose more radiator fluid though if I take longer trips.
Any easy fixes? Thanks for the help.