My bmw 7 series is overheating?

my 7 series was garaged for a replacement head ,3 weeks later its back in for the same problem i noticed the rad hoses where solid ,under pressure and even releasing the rad cap 8 hrs later there was still pressure could exhaust gases be getting in to coolent therfore the the gaskets gone again ,any answers appreciated thanks ,the car is 1996 2.8i 7 series

My bmw 7 series is overheating?live update

The system holding pressure like that is actually a good sign. If the head gasket had failed again the system should build pressure IMMEDIATELY but bleed it well within an hour.

If the car is overheating while idling or in slow traffic the viscous cooling fan clutch has failed.

If the car is overheating under load the thermostat or radiator are defective.

If the car is overheating all the time it may be low on coolant or the cooling system was not bled correctly.

First you need to bleed the system:

Top up the expansion tank with a 50/50 coolant mix and have a couple of litres on hand.

Remove the little screw (bleed screw) on the top side of the expansion tank. Compress the upper rad hose with your hand. Place your thumb over the bleed screw hole and release the upper rad hose. Do this repeatedly until no air comes out the bleed hole... only coolant with no bubbles. keep the expansion tank topped up.