It is your thermostat housing that is cracked at the seem and leaking. Buy a new one and it will solve your problem. O-ring is all you need.
What is everyone using to seal the thermostat housing. The o-ring and plastic housing obviously don't cut it.
I made a gasket for the thermostat to housing mating surface, plus a new o-ring, but I still have a leak. If I have to take those bolts out again I'm gonna go nuts.
It is your thermostat housing that is cracked at the seem and leaking. Buy a new one and it will solve your problem. O-ring is all you need.
Be sure to purchase a metal housing instead of the factory housing that is plastic.
thats all folks.
95 E34 530I V2.37
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Those who make peaceful revolution impossible will make violent revolution inevitable.
John F. Kennedy
I hate plastic parts. I didn't see a crack in it, however it didn't sit flush against the thermostat. That's why I added a gasket to that side. Crap now I have to wait for more parts.
If it doesn't sit flush then your thermostat is not in the right position.
When a new o-ring is installed, the cover should sit a mm or two away from the head or in this case the water pump. Once its torqued down the o-ring gets squashed thus it seals.
Sure the O ring was in the right place? Thermostat sits flush against the waterpump flange, then the O ring, then the housing....