upper radiator hose blew off

[Redfrog]

I just bought a 1989 1/2 ton 4x4 that is bone stock, that about 5 hours ago the previous owner said it was running and driving perfectly fine as he was driving down the intertsate. that was until the upper hose blew off
the raditor. he told me last week it started to run hot on him so he changed out the t-stat and radiator cap, and all was fine. fast foward to this afternoon he was doing about 70mph heard a load pop and then smoke. when he popped the hood and the hose was off, and the overflow was full.

What could cause this, there is no water in the oil, no sweet smells out of the exhaust, when he dropped it off I dumped a gallon or so of water in it and fired it up, it bubbled and spewed until I shut it off, but ran as smooth as a new engine.

I figure it is a bad head gasket but I am not sure anyone care to guess.

 

[76K20]

Did he recently put new hoses? When worm clamps are used they have a tendency to back off a little bit until the hoses are properly settled.

 

[Thunder]

Bad head gasket or cracked head. Common problem with TBI V8s

 

[Redfrog]

well after doing a few checks it looks like a head gasket or head like thunder said, I added some more water and as I was doing so "steam"
for lack of a better came raising out of the radiator, although the engine was cool. so I smelled the it and the radiator smells like exhaust so I guess the heads are coming off.

 

[toomany]

It could be a simple as the clamps are worn out/not tight enough. If they are factory style spring clamps....toss them out and put some worn drive ones on. If they are worm drive, check to see if the metal that captures the screw isn't bent up. This would allow the screw to move around and loosen the clamp.

EDIT: For some reason posts number 3 and 4 didn't weren't showing up when I posted this.

If you are thinking it's a head or gasket. It wouldn't hurt to do a leak down test first.