Cooling system leak

[Lamar B. Dale III]

I recently experienced a sudden cooling system leak that seem to be coming from the water pump area. I'm a mechanical engineer crossed with a shade tree mechanic, which means I have the ability, but not the tools. I jumped in and changed the pump, as well as the thermostat and fan clutch while I was into it. It wasn't easy, but I got everything back together only to find I still have the same leak and it's not the pump. I'm afraid to think what it might be, so I came here hoping someone might relieve my worst fears.

 

[BrooklynBay]

Welcome to this forum! Connect a cooling system pressure tester to locate the leak.

 

[Mr. Alligator]

Plastic thermostat housing failures are a common problem.

Good luck

 

[koda2000]

Plastic thermostat housing. Very common problem with the 4.0L SOHC engine. Metal replacements (both one piece and two piece versions) are available but are pricey. Plastic replacements run from about $20 to around $80.

Here's a pic of basically what the part looks like, but you may have the push-in sensor/sender rather than the screw-in type.

 

[swshawaii]

4.0 SOHC Metal Thermostat Housing Comparison

Explorer Mountaineer 4.0L SOHC Thermostat Housing w/Sensors Hose/Clamps/Bolts | eBay

**01-06 sport trac & Ranger 4.0* 2 sensor**plus 2 clips, 2 gaskets*Made in USA* | eBay