Nissan Repair: My 1995 240 SX, service receipts, head gasket

Question
My car has 96,000 miles and was stalling when I shifted gears. I brought the car to a new mechanic. He said it did NOT stall for him at all. He said it looked like it could use a tune-up. My service receipts showed it hadn't had a tune-up in 40,000 miles so I agreed. Got the car back and drove it for 10 days until it stalled again. I also noticed that the temp. gauge was on HOT. I pulled off the road into service station. Radiator & Anti-freeze container were both bone dry. He filled them both with water(to see if they leaked) and they did not so I was able to drive the car home(couple miles away). I brought the car back to mechanic and told story. I asked if he checked the radiator during the tune-up. He said maybe not - don't always check that on a tune-up. He checked the car and said the water pump was leaking so he installed new one. He called to say the car is fine now when it's idling but driving anything over a few miles, the car still overheats. Now he thinks it's a head gasket. He said there is air getting into the radiator causing the car to overheat. I paid for the work and now have a car that I can't drive. Should he have checked the anti-freeze during the tune-up? He did replace the thermostat. Do you think it needs a head gasket? He says that is about $1200. Is that right? Please advise. Do I need a new car???? HELP!  

Answer
hi ellen, please email me @ xxp_sebby@yahoo.com.  thank you.  i will go over this with you in email.

*EDIT*  anytime you may think its a headgasket failure its best to get a hydrocarbon test done at a qualified garage.  its a failsafe method of detecting gases in your coolant (leaky headgaskets).  another surefire way to tell is a THICK constant white smoke out your tailpipe.  and labor is extensive in the 2.4 twin cam 240sx motors when changing the headgaskets.