Mysterious coolant leak after changing mono valve

[Dudernio]

1987 300SDL
While changing the mono valve, when I lifted the unit out of the housing, suddenly there was an instant release of coolant from underneath the vehicle somewhere. This coolant did not come bubbling out of the top of the mono valve housing as would seem logical. Never happened before on any other car I've performed this same procedure on. There are no apparent leaks in the system that I know of. Looking at the puddle on the ground I estimate a pint or so of coolant. I put the new mono valve in, drove around. No leaks. So what was it?

[86-300sdl]

My 86 SDL did the same thing when replacing the monovalve. Twice now 'cuase the first replacement was defective.

I'd guess about a pint spilled over the housing edge kind of burp wise.

I think your fine

[Dudernio]

That's what I'm replacing the monovalve again, the first one I put in a few months ago and realized it was defective out of the box. Just finally getting around to replacing it, with a used one I know works.