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MG MGB Technical - to much water pressure

hey everyone my 76 mgb's water pressure is so high that it looks like the top radiator hose is about to explode and its a new hose does anyone have any ideas?

thanks in advance

scot
Scot Hamm

Scot, you have one of two problems and they both are in your radiator cap. A. You either have the wrong length radiator cap or B. You have the correct length radiator cap, but the wrong pressure relief.

Mark
M Whitt

You may also have a bad head gasket which is allowing your cooling system to be overpressurized by the pistons filling the radiator with combustion pressure. If you have lots of bubbles in the radiator, this is a real probability. Ray
RAY

I bought the cap from moss motors and it said it was for the 76 however i notice that i cant find a leak and the water is dissapearing while i run it. The car also is blowing white smoke but this is the first time its run since 1989 so i figured the rings needed to break in
Scot Hamm

Scot:

It would appear that Ray has the answer.

Jack
J.C. Weidner

I also concur with Ray, it sounds like a blown headgasket to me too.
M Whitt

I'll throw my vote in with Ray and the blown head gasket, which makes it unanimous, so (unless somebody demands a recount) it is head removal time. The loss of coolant and the white smoke is about all the diagnosis needed. Take the car to a radiator shop and let them put their exhaust gas sniffer in the radiator filler neck to confirm this. Cheers - Dave
David DuBois

thanks guys i went to change the head gasket out today but the head was frozen with the studs so im going to remove all of the studs tomorrow
Scot Hamm

Be sure to change your oil and drain your oil cooler as you may have water in your oil as well - it may have bubbles in it or appear milky white to some degree.

Just a thought
J Delk

Scott,
If you have been running for a while with the white smoke (= steam) coming from the exhaust and the water has been getting into the oil, then the emulsified gunk will be throughout the engine.
It is a good idea to flush the engine with a couple of oil changes to get rid of this.
I recently had to do this with a V6 Toyota engine, and used a 50% diesel 50% cheap oil blend (Note: at idle only).
David
David Overington

This thread was discussed between 25/02/2007 and 04/03/2007

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