Oil leaking out of Thermostat - Help

[sayah]

The internal thermostat is leaking all over the top of my newly rebuilt 911E engine. Replaced the "o" ring with one supplied by our host (orange), but this has not helped.

In reading other posts, it seems that the only way to fix this problem is to get one directly from the dealer. The one I want is suppost to be green!

Just for some background, I did the oil bypass modification, and upgraded to the newer pressure relief pistons and springs.

Thanks for your help guys!

[126coupe]

Not sure if this would cause the leak, but did you put it in ass backwards? The 2 cut outs should line up

[john walker's workshop]

red seals are softer than the green ones. i've had issues with those too, years ago, so i don't use them anymore. the thermostat only fits one way. the studs are offset.