I recently installed a new 180* stat(stock 192* as indicated) and I took it for a test drive, however when I came back I noticed the upper and lower radiator hoses swollen at the point where they meet the motor(swollen from the clamp), though I admit I didn't top out my radiator with coolant after the swap and whatever coolant that leaked out was left out of my system before I ran it, due to my excitement to just drive yea dumb move I know... and I noticed it sucked all of the coolant from the expansion tank as well. My car didn't over heat or go in the red at all. It went to 220 in traffic but went down to normal again once I started moving, would this swelling be caused by air in my system? Perhaps the hoses are to old to withstand the flow of the new thermostat?? Time for new hoses I guess as well. I doubt its a head gasket issue. Idk.. any input??

 

Sounds like you need new hoses.

No it is not caused by air. It is caused by the rubber being all old and soft and rotten, and the reinforcing threads in it being all turned to dust, and the pressure that the cooling system is designed to build up (about 16 psi or so... look at your rad cap) is blowing them up like a balloon.

Your description of the temp and its variation in traffic sounds completely normal.

 

Thanks for the reply, yea I put new hoses and all fixed, your were right the inside of the hoses looked horrible especially the bottom one with the spring, it must have been stock from 1985! so far I ve replaced the radiator (lifetime warranty from o reillys) and the aforementioned stat now the hoses. Cooling system should be ok for awhile now. Thanks again!