Hi my car is leaking water on left side of engine. I want to take that big black plastic thing off the top of the engin but dont know what size bolts they are. Are they metric or imperial, and what is the size please? There are about 5 maybe 6 deep set bolts holding this thing down. I dont know what the leak is, but its wet by the top left side plastic thing with water air bleed valve on top with several water hoses going into it. I am windering if this is cracked.
any suggestions welcome, but i need to know bolt size to buy tool. Is this a special deep socket or something, because i tried so many sockets and nothing fit.

there is no water in the engine oil. So what else can this leak be from? I have 165,000km on engine, and runs perfectly on syntehtic oil always. I know chrysler techs have helped me before. Look forward to hearing from you all.
thank you
gpatel