Losing water on 740 GL. very low mieage (49,008 miles). Radiator hoses get very pressurized (very hard!!) Temp. guage working OK, but if you undo pressure cap to relieve pressure and allow hoses to go back to normal, will need to put in about 2 pints of water to top up.
Pressure cap is new.

Any ideas? Stat? Head Gasket? NO signs of water in oil of from exhaust and no obvious leaks found/seen.

There have been numerous reports on this board and I have experienced myself, aftermarket overflow tank caps which allow excess pressure to build(far in excess of thier stated capacity). If you have placed one on your car and then symptoms began very shortly thereafter...go to junkyard and find an old OEM Volvo "Black" overflow cap(240, 740, 940) and install it. If symptoms persist(actually regardless) see where coolant is leaking from as it is a weak point. I find a led flashlight, at night, to be quite useful in locating such leaks. Look 1/3 of the way down engine block all the way around for starters...its going somewhere.
Look for drops on the ground/in the snow for clues, after a good hard run, and subsequent cooldown. Its going somewhere!

Most common leaks, piping out of the back of the water pump to heater core. And the top of waterpump, oring gasket.
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