I can drive the car for how ever long I want and it runs fine and does not over heat. I shut the car off and not long after it does theupper radiator hose starts to collapse. What causes this and how do I fix it? The line to the over flow tank is not blocked. Maybe a bad radiator cap? I put in some stop leak with the pellets not long ago in attempt to fix a small seepage (nothing major, just a nit-pick thing) with no success. I want to change the antifreeze now so can I just use regular antifreeze or do I have to use honda antifreeze? Thanks

 

regular green antifreeze is just fine. So you are saying that the upper radiator hose is squeezing shut after the car has been turned off? Sounds like some kind of vacuum is getting into your cooling system

 

I think it's a simple law of some sort in physics or chemistrythat when something is heated, then it cools and condenses. I'm thinking the radiator cap lets so much go into the over flow tank then it is jammed somewhere and doesn't let the fluid back into the radiator. Then I take off the cap and the hose is no longer squeezed shut. I'll try cleaning the cap and see what I get.

 

The radiator sucks water back from the overflow tank when the engine cools off. If the hose is collapsing then something is blocking the coolant return. If the hose is old and soft, that could do it too, but I would first eliminate the clogged line possibility.