Cooling system pressure

[Tex Law]

Just purchased a 90 Festy 5 speed. Love it. While driving the other day, the thermostat bypass hose leaked down most of the coolant before I smelled the trouble. After replacing the hose and reloading the system...now when I crank her up, there's so much pressure in the cooling system that it will literally blow the overflow hose off and shoot coolant about 6 feet. Would it be safe to assume the head gasket is cracked between a combustion chamber and a water tunnel ?
Thanks,
Tex

[lessersivad]

Best case is blown head gasket. But it could possibly be a warped or cracked head.

[bravekozak]

check thermostat

Before jumping to worst case scenario, doomsday event, I would check your thermostat to see if it opens as it should.

[lessersivad]

Before jumping to worst case scenario, doomsday event, I would check your thermostat to see if it opens as it should.

Yea, I guess if it takes awhile to build pressure that may be a good starting point. But if it builds pressure rather quickly after say, sitting all night, then I'd have to go with my first post.

[Tex Law]

Thanks for the replies.
I'm hoping its just the gasket between the tunnel and the chamber. Don't really mind changing it out, gives me the opportunity to replace the timing belt and water pump. Who knows when and if they've been done. Damn 4 banger's got 293 K on the clock and runs great.
Tex

[blkfordsedan]

Seems to me if it's blowing compression into the water that bad you would have water in the oil, steam out the exhaust, smell of burning anti-freeze or something. At least there should be other tell-tale signs.

[Festy46]

Take your water pump belt off and fill the radiator to the bottom of the radiator neck. Leave the cap off and start the car. If the water immediately starts overflowing the radiator or you see bubbles of air coming up through the water, you have a compression leak into the cooling system.