Inflated upper radiator hose? M104

[juribe2]

Hi,

I replaced all radiator hoses (upper, lower, bypass) 6 moths ago. A couple of days ago, I noticed that when the engine is hot (90 - 100C), the upper radiatior hose gets inflated. I thougt that the system pressure was supposed to be absorved by the expansion tank and not by the hoses.

Do you think this is normal or should the hoses keep the same diameter when hot?

Almost forgot: I also replaced the expansion tank, the exp. tank cap and the termostat 6 months ago. The exp. tank look good but I think it is not releasing pressure as it is supposed to.

Thank you,

Juan