jeeperguy21
NAXJA Forum User
- Location
- Syracuse, UT
I must say that there are a lot of cooling system threads. I searched over two years' worth but with to no avail for this specific question.
First off, I understand that the pressure in the cooling system is regulated by the radiator cap. I have a '99 4.0 w/ 150k on the clock. Radiator cap is a few years old. Pressure tested it a few months ago and it checked out fine.
I have been slowly losing coolant for a little while now and decided to do a little investigating today. After going for a nice drive today for about a half hour, stop and go city driving, I came home, popped the hood with the XJ still running, and noticed that I have no pressure in the system. I squeezed the upper radiator hose and it's a soft as a limp noodle.
I feared that the radiator was deathly low on coolant, so I shut down the engine, verified that there was no pressure by squeezing the hose again, and removed the radiator cap. To my surprise, the radiator is completely full, as well as the overflow bottle. I have had no overheating issues and the Jeep's temperature has been normal with no unusual symptoms. I am going to go pick up a new radiator cap right away, but am wondering if there is anything else that could be causing this to happen? Water pump and thermostat are both less than 1 year old as well.
First off, I understand that the pressure in the cooling system is regulated by the radiator cap. I have a '99 4.0 w/ 150k on the clock. Radiator cap is a few years old. Pressure tested it a few months ago and it checked out fine.
I have been slowly losing coolant for a little while now and decided to do a little investigating today. After going for a nice drive today for about a half hour, stop and go city driving, I came home, popped the hood with the XJ still running, and noticed that I have no pressure in the system. I squeezed the upper radiator hose and it's a soft as a limp noodle.
I feared that the radiator was deathly low on coolant, so I shut down the engine, verified that there was no pressure by squeezing the hose again, and removed the radiator cap. To my surprise, the radiator is completely full, as well as the overflow bottle. I have had no overheating issues and the Jeep's temperature has been normal with no unusual symptoms. I am going to go pick up a new radiator cap right away, but am wondering if there is anything else that could be causing this to happen? Water pump and thermostat are both less than 1 year old as well.