Focus Fanatics Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
8 Posts
Discussion Starter · #1 ·
Coolant leaked bone dry.. Seemed like it was coming from the 90 degree angle pipe next to the tstat housing.. Thats not part the cooling system as I've discovered.. must be leaking from the tstat housing? I removed and inspected the tstat housing and it seemed to be fine.. no cracks etc.. Ive replaced this part before, it failed horribly a couple of years ago.

I replaced the tstat and gasket and housing o ring.. replaced.. STILL leaking.. now I noticed a leak from the bottom bolt in the housing..

Is this most likely this issue? Will a new housing fix it? The fluid is all dripping off that pcv pipe and then down the tranny...It seems to be a substantial leak.

Any help would be greatly appreciated.
 

Attachments

·
Registered
Joined
·
2,595 Posts
I'm guessing this is on a ZETEC motor? What exactly did you remove and inspect? Just the outlet or did you take the entire housing off the head? The housings aren't exactly serviceable. Its best to replace the entire unit. Go to a parts store and get Dorman part #902-200

Also is there any oil leaking down from the valve cover? Oil getting to the seal is the most common cause of leaks. Rubber doesn't get along with oil very well. If there is any oil leaking replace the valve cover gasket as well. Fel-Pro #VS50553R
 

·
Registered
2004 Focus Wagon, Zetec DOHC, Auto
Joined
·
1,612 Posts
...any oil leaking down from the valve cover? Oil getting to the seal is the most common cause of leaks. Rubber doesn't get along with oil very well.
I'm curious. Is that just a rumor that has been repeated so many times that it has become "fact", or is there something to it? After all, the valve cover gasket is rubber.

My thermostat housing failed. It was cracked and chipped on the inside lip of the o-ring seat. One small crack made its way to the outside and that is where my leak began. I wouldn't attribute my failure to oil even though there was oil on it. I attribute my failure to deterioration of the plastic housing with time and exposure to high temperatures being the contributing factors.
 

·
Registered
Joined
·
17,561 Posts
The stat housing/head seal is silicone (high temp for the coolant temp) rubber as well, just different color because they are dyed. I let mine soak in oil leaks when I don't get around to them for a while and no trouble at all. As well, I've found many failed seals there but they all had one hundred percent density to them, oil soaked seals get like mushy, the rubber is breaking down into the base oils. Never seen that on a stat seal before, they will simply be deformed all out of shape.

All rumor passed down until I see different.......................the cam seals are rubber, the VCT seal is rubber, the VCT cylinder internal seals are rubber, etc., etc.
 

·
Registered
Joined
·
8 Posts
Discussion Starter · #6 ·
Update

After removing the housing again and re-inspecting I did find a crack on the inside that apparently I had missed the first time. Replaced the entire housing, problem solved.. This is however the second housing for this car in five years.
 

·
Registered
Joined
·
17,561 Posts
The later RE-design like you have absolutely sucks and why did those idiots do that?? The plastic was changed to be weaker and the front bolt pattern was changed to be borderline stupid, and why they fail. If it does it again go to the '98-'00 Contour zetec stat housing and you will not change it again, much better part, like said WHY did they change it???

You will not see 80% of the cracking on the later part until you throw a bit of fine sandpaper on surfaces to smooth things up, the inherent roughness of the beginning-to-degrade part hides the cracks. If you can scrape with fingernail to pull up crumbling plastic the part is shot, crack or no. But use the sand paper like I said, use sunlight or strong light then and you will commonly find another 4-5 cracks you did not see before. It's NEVER just one..............
 
1 - 7 of 7 Posts
Top