TOP hose cool BOTTOM hose hot?

biggyfan1

Member
Mar 10, 2006
186
1
18
High Desert CA
TOP hose HOT BOTTOM hose COOL?

On my 66 mustang i have been starting it once or twice a week for about 10 min's each time. So far it has NOT gotten hot but i do notice the top radiator hose is hot and the bottom is way way cooler is that normal? thecar does not drive yet because i need a torque converter but i still go out and start her just to do it.
 
Sounds like its working right to me.

Water comes in at the top and gets cooled as it travels thru the rad and out the bottom.

Somebody correct me if I`m wrong, I`m a newbie myself.
 
+1

if it wasn't, you would be screwed if your water level was low, of course, I've seen ford engineers do dumber things :rlaugh:

the actual reason why its on the btm (besides not running out of h2o) is that colder water is heaver, and sinks to the bottom. i believe that this is also the reason why the trans cooler line is on the bottom??
 
I do not think in water circulation it matters that cold water would "sink". The reason is that the water is cooled as it goes down through the radiator. The reason the tranny lines run there is because that is where it's cooler, but not because cold water "sinks" down there.

Funny that your title says the bottom hose gets hot and in the thread you say the top one does :-D
 
The top hose gets hot because the water pump is trying to push water into the block, up through the heads, out of the intake, and into the top of the radiator. When the water behind the thermostat gets hot enough, the thermostat opens and lets hot water into the upper hose. When the cool water goes up though and hits the thermostat, it closes, and keeps doing so until the whole cooling system reaches a point of equilibrium.

Also, stop letting it run in place so often. You stand to do more harm than good by idling it so much and not letting everything get up to operating temp.