Cooling line pressure builds up

SPAREDES

MEMBER
1993 CADILLAC FLEETWOOD
5.7L
V8
RWD
AUTOMATIC
180,000 MILES

I changed the water pump, radiator, thermostat and radiator cap on my car, because car was overheating. So car is not overheating but five to ten minutes having it turned on pressure builds up on one of the hoses that is connected to the water pump and starts to leak. So I turn car of before it bursts. Please help I do not know what else could be wrong. Engine sounds nice and strong no white smoke no leaks of oil or coolant anywhere. My only guess is that it has a clog somewhere. Coolant has rusty color.

1 Reply

HARRY P

MECHANIC
2,293 POSTS

What is hose connected to? Does it go to the firewall? Or somewhere else? If it goes to the firewall, then that would be a heater core hose, and the core could have gotten clogged with rust, dirt, and debris. I would take both of those hoses off from the engine side, connect my water hose to the hose that is not leaking, point the other somewhere where it will not get anything important wet (maybe into a bucket or something), and turn the water hose on with low pressure. That will push the crud out slowly if that is the problem.

Also, if you have not ever changed the clamps on the cooling system hoses, it might be time to do that. Over the years they stretch just a little and become weaker, causing little leaks kind of like this.

Let us know.