Coolant leak.

[gdgiordano]

i have a leak high up in my SOHC somewhere. I took it to the shop and they whipped a bunch of coolant out of the trough between the headers. They pressure tested it with no leaks and this was all the day after I had antifreeze pouring out the front tray under the radiator. The leak does seem to be Worse when it is 15 or below. Also the leak seems to slow/stop once the vehicle is warm. Ideas?

 

[swshawaii]

When a 4.0L SOHC has a coolant leak, always start by inspecting the plastic lower thermostat housing. They are known to split
at the seams, and earlier versions had threaded sensors that leak. There is an upgrade linked below using a less expensive newer housing with non threaded sensors.

http://www.explorerforum.com/forums/showthread.php?t=396922&highlight=lower+thermostat+housing

http://www.explorerforum.com/forums/showthread.php?t=239493

 

[rb142]

Thermostat housing first. Also check the hose connections, as coolant can run along hoses for quite a while and look like a leak in a different location.

It should be easy to find a coolant leak with a pressure test. If it only happens when cold, then tell your mechanic to get off his butt and go pressure test it outside in the cold.

 

[gdgiordano]

We found it. It was a broken radiator that didn't even leak under a pressure test.