Land Rover Repair: Overheating Discovery 2000, radiator fluid, head gasket

Question
I readyour blog on engine failure and appreciate all the knowledge.  Over the summer my ac went out.  Recharged it and went out again.  Hearing that famous swooshing sound when turning.  Heat went out this winter.  Went through the easy items first.  Bleed the system twice.  Drained the radiator fluid and low pressure flush.  Replaced the themostat and cap.  Beed system again.  After a couple of days noticed it did not help.  Not seeing any visible signs of fluid leaking.  Car has a slight oil leak. Oil not tainted w/ radiator fluid.  Need to pressure test the radiator and the block.  Is that something only a mechaninc can do or can i rig something?  Any other ideas?  If it is the engine, the car goes ba bye.  Dont want to do the head gasket unless i know it will fix it.
Thanks

Answer
Well, you are in a fix.  The only way to test the engine block is to remove it from the vehicle and take it totally apart.  And no one in his right mind would guarantee a head gasket change.  What you can do is pressure test the whole system for external leaks.  DO that hot and cold by using a pressure tester screwed onto the radiator expansion tank cap.  I suppose anyone can pressure test the expansion tank, but will you know where to look for leaks, etc?  It seems like a big decision to make yourself in the back yard . . .

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