Now my turn, coolant leak

[PAExplorerXLT]

I have been reading about thermostats and water pumps etc. but looks like it is my turn now. This morning I noticed green liquid on the ground. The highest point on the engine that I could see coolant leaking (I assume it is coolant) is on the passenger side below the exhaust manifold. I took a picture from underneath the car. Experts here would probably know where it is at.

https://www.dropbox.com/s/1mtdfqkhbu9wa9j/2014-12-14 12.01.02.jpg?dl=0

 

[drdoom]

Pa I had a leak for the longest time, couldn't quite see where it was coming from, except looking up from underneath it looked like where the passenger side head meets the block. Finally one day a pinhole stream shot out from the thermo housing, and that is where it was coming from all along. Look there.

 

[swshawaii]

Thermostat housing leaking

http://www.explorerforum.com/forums/showthread.php?t=416538&highlight=lower+thermostat+housing

 

[Peanut74]

Ditto on the lower thermostat housing leaking. Just to be sure get a bright flashlight and check where the passenger side head and intake mate up. There are a couple of spots where coolant will pool if the housing is leaking. It is a PITA to replace but do able.

 

[PAExplorerXLT]

I dropped the truck at my local shop tonight so I should know tomorrow. Any diagnosis that has the word “head” in it scares me. Could it really be the cylinder head? If it is the thermostat housing, what do you think it’ll cost me? Isn’t the thermostat on top of the engine. I can see a black plastic housing that looks like it.

 

[PAExplorerXLT]

Ditto on the lower thermostat housing leaking. Just to be sure get a bright flashlight and check where the passenger side head and intake mate up. There are a couple of spots where coolant will pool if the housing is leaking. It is a PITA to replace but do able.

The links I looked up all show the thermostat on top of the engine. It looked dry to me. The first sign of coolant I saw was below the exhaust manifold. What is meant by “lower”? As in the lower piece of the housing?

 

[koda2000]

The links I looked up all show the thermostat on top of the engine. It looked dry to me. The first sign of coolant I saw was below the exhaust manifold. What is meant by “lower”? As in the lower piece of the housing?

the SOHC's plastic thermostat housing consists of 2 pieces the UPPER and the LOWER sections. the upper is where the rad hose connects, the lower is attached to the engine. the plastic housing seems to always develop leaks sooner or later because it cracks or the senor/sender's leak. someone is now making an all metal housing (for Mustangs) which is a much better design. it isn't cheap, but neither is the OE plastic housing.

 

[PAExplorerXLT]

What if you have coolant loss and the thermostat housing is dry? The leak appears way down.

 

[koda2000]

One of my V8's developed a coolant leak in the same general area. It only leaked when cold and the colder the outside temp, the more it leaked. In my case I believe it was the timing cover gasket on the passenger side that was leaking. As replacing that gasket is a major PITA (and the engine now has over 200K with no other problems) I decided to try a sealant product that was recommended by a friend. It's called K-Seal and cost about $12-$14 for 8 ounces. I drained off a little of the coolant from the radiator, shook the bottle well, as directed, and poured it in. It looks like chocolate milk with cookie crumbs in it. Then I refilled the rad and idled the engine for 1/2 an hour. It hasn't leaked a drop since. My friend reports that he used it quite a long time ago and his leak has never returned. K-Seal is supposed to permanently seal all kinds of coolant leaks and so far so good. I'm not recommending you use this product, but it worked for me and saved me a lot of time and money.