YesterdayI discovered that my reservoir was empty so obviously I filled it up only for it to become empty again. I found that the plastic ring had failed on the filler neck on the upper hose( Im sorry I forgot to mention I have an 01 Durango with a 4.7) anyhow, I bought a new hose,filler neck and cap and installed them but it really doesnt seem like the coolant is flowing through it still. I asked the guy at advanced auto about the long spring inside of the hose and he told me I didnt need it, so I didnt install it, dont know if that is going to hurt anything,anyways it seems like a lot of pressure is building up in the upper hose because the new setup is leaking out from the brand new spring type clamps still when it gets hot, its just a small leak, but still, brand new clamps shouldnt be leaking. I was wondering if it could be the thermostat, but that is located in the lower hose on my engine so that isnt making much sense to me. I should also say that the small hose going from the filler neck to the reservoir is NOT hooked up right now because when I cut it there was no extra slack in it so it doesnt reach now and I didnt have time to buy the new one before the store closed. The funny thing is though that even with the vehicle getting hot and the hose leaking under pressure, no fluid is exiting from the hole on the neck where the radiator cap is. Shouldnt coolant be coming out of that hole when the cap gets too hot? Any idead on what my problem is would be appreciated. Im intending on replacing that small hose obviously today and picking up a new T-stat and then I guess my next step is the water pump, but I need some advice from people who know what theyre doing because I do not, and I am starting to sweat.
Thanks!!

 

did you replace the radiator cap when you replaced the hose? if so what is the pressure rating on it?

that spring from inside the top hose is there to stop the top hose from collapsing under negative pressure, it is there for a good reason i would make sure it is installed, and also trusting people at advance, auto zone, napa, pep boys, ect (any chain parts store) is a bad idea, all they are are (most of the time) is computer jockeys who know little if anything about cars, i wouldnt trust them to change my oil.

also check for the hose which goes from the radiator cap to the overflow, this NEEDS to be hooked up, and also make sure it is not clogged.