I am embarrassed that I cannot locate the leak. It happens when fully warm, at cruise (60-65 mph). It SEEMS to be at the junction of the thermostat housing and the block, at the base of the valve cover (front and center).

But, when fully warm, with a stick braced on the throttle at 2800 rpm, no evidence. Cruise down the hiway, gets warm, you can smell it, get out and there are very limited "spots" of spray on hoses. Topside only, And residue at the front/center location. I have pressed fittings, squeezed hoses, no luck. Some corrosive looking areas on the thermostat housing under the temp sensor leads area. I even suspected a tiny crack in one of the heater hose metal tubes, but no luck.

Thanks for any suggestions

Any suggestions?

Rxfire--

I had my n/a C223 leak from the thermostat housing and tightening it did no good. So, I removed the t'stat housing from the head and found some corrosion on the gasket faces. But, worse, I found that the t'stat housing gasket face was badly warped; ie, not flat. It is a fairly thin section and there are only four bolts to hold it down, looks like a recipe for warpage.

What I did was to use a large piece of very sharp abrasive paper on a flat plate to cut the surface down to flat, and this cured the leak. This had to be seven plus years ago.

I like Permatex #2 for gaskets like this.

Paul

Thanks Paul. I have another junk engine, I can pull both, select the best, shave that one if needed, and I might as well put a new thermostat in while I am there. That seems to be the area, and would open up when hot. Permatex #2!

Rxfire--

OK, good deal. Keep us posted on how this works.

Paul