I just noticed a few days ago that I have a coolant leak. I've checked all the hoses and radiator. No problems there that I can see. It's a dripping kind of leak. I end up having a puddle under the engine, maybe a little bit to the passenger side. One thing I did notice when I was looking around with a flashlight is a very wet spot a little bit behind where the thermostat housing is. It's within the engine in a hard spot to see. I'm pretty sure it's not coming from the thermostat itself as I also checked that. It's maybe 4 or 5 inches behind that. Looks like that might be where it is coming from. Is that in an area where one of the head bolts could be and maybe it's a loose head bolt? I'm just throwing things out there as I have no idea what it could be. Anyway, thanks for any help with this.

 

OK, just to update. I decided to stop at my mechanic this morning to have him take a look at it. Turns out that it is the thermostat housing that is leaking. He told me that with parts and labor it would probably be about $300 worst case scenario. I replaced the thermostat once in my old ranger. Wasn't real difficult. How much would be involved if I tackle this myself? I'd like to try and save some money. Thanks for any replies.

 

The upper housing and gasket is $13.04 on rockauto for a Motorcraft part. The lower housing is $33 for a Motorcraft part as well. I don't know how hard of a project it is, but maybe someone else can say if its worth $250 in labor to let a mechanic handle it.

 

I did the upper and lower t-stat housing last summer, it isn't difficult. Would be easier access if the TB is removed but not required. Some of the hose clamps suck to get loosened they're in a tight spot. While you're in there replace all seals and gaskets, there's one between the lower housing and block, and one on each temperature sensor, and one for the t-stat. Check the sensor wiring, I had to replace some of the wiring the insulation was peeling and bare wires.