problem with hoses pressure of the cooling system

[PABLO]

hey guys, I'm from argentina, I have a bmw e34 520i 1989, I had some problems with the cooling system (antifreezing). I had to change the thermostat, water pump, hoses, i had even to repair the radiator (not new because here in argentina the dollar is getting expensive 1:3) Here the problem: I noticed that the hoses have too much pressure, they are as hard as a tennis ball or a little bit less. I asked to many official Bmw mechanics about this and they have so many differents opinions that i dont know what to do. (some of them said this was normal)
Is it normal that pressure? Should they be with no pressure at all?
Would this pressure brake something of the engine or cooling system? How is the normal pressure?
Thanks
Pablo

pd: Please excuse me if i made some mistakes in the the text.
Thanks again for your patience.

[gvilkelis]

The cooling has to have pressure, because the coolant will start boilling at higher temperture if under pressure.
My E34 '88 hoses are on pressure too, but I do not know how much pressure would be normal.
I guess, the cooler expansion tank cap is responsible for releasing the extra pressure from the system.

[632 Regal]

ahhh Pablo! now I see what your asking, yes the hoses are hard at operating temperature, this is a normal situation. If the car repeatedly blows hoses and parts without the temperature gage going into the hot zone you may have a head gasket leak that is pumping compression into the coolant system, it also means that the pressure cap is bad.
Good luck!

[PABLO]

thank you very much guys, i really preciate your opinior. It was very useful to me.