Hey guys, just recently did waterpump, new 3core alum rad and new hoses and new 13lb cap. Truk is a 91 7.3 n/a
after a bit of driving i notice my rad is very! Hot to the touch (i assume around 190f or so), stock ****ty gauge reads ok and truck drives fine, but the upper rad hose is very firm even after shutdown untill the truck cools down. Is this normal? Or is there still an air bubble somewhere? i only had the mech fan fully lick on once when i was doing in town driving for 5 hours with a fully unlocked converter.

 

Sounds right to me. Top hose should stay hot and firm after the t-stat opens, and it can take a while after you shut the truck down for it to come back to ambient.

Mike

 

I got a question to, instead of starting a thread for it, it's basicly the same as this.


My upper rad hose, sucks it's self in when revving the engine..... but feels firm and normal cold/engine off.


Whats the deal with that? Tired rad hose?

 

OP- you have nothing to worry about. that is normal.

John- pretty sure the only way for that to happen would be water pump spinning in wrong direction. do you have the belt on the correct way?

 

This is an easy one.

You need a new radiator cap. Yours is not allowing coolant back in from the overflow bottle causing a vacuum in the radiator therefore collapsing the hose.

 

Thanks! I'll get a new one for it. Wouldn't hurt anyways, the one there looks original.

 

check the overflow tank hose for any obstruction as well.

 

I guess the bad rad cap would also explain the missing gallon of coolant in the rad when I bought this van. Doesn't have any coolant leaks, so with a rad cap not holding pressure, it was just boiling out of the system.