[turbo_911]

I noticed that my car is leaking coolant only when I come home after a drive. When the car is cold, nothing is leaking, only when warm. It is dripping VERY slow and overnight you probably will get less than a tea spoon full.

Now the question is, is there any way to trace the leak without taking apart everything?
I've attached two pictures two show where it is leaking from.

In April 2011, by previous owner, water pump, thermostat housing (alum), thermostat, lower radiator hose were replaced. I don't know what kind of water pump it is. I bought the car in August 2011 and have receipts from work. It says it was $85 for pump. Must be OEM? Could it be leaking?

[sharpie]

Assuming the first pic is the front of the oil pan - yes it could be the water pump, but it could also be the thermostat housing. You should probably at least take the fan and clutch off to see.

[MMMGP]

Taking the fan off, then the belt, and finally the water pump pulley is no big deal. A few minutes of work and you should be able to see exactly where the leak is coming from.

I have read stories here of the aluminum stat housing leaking... dig into it.

[turbo_911]

It would be easy if I had a fan lock tool but since I don't, that's why it was worth a try ask to see if there is any other way to find out what's leaking without taking everything apart

[MMMGP]

Yeah, I bought the lock tool years ago. It's a must have. BTW, I thought BMW coolant was blue, not green.

[bimmaboy88]

don't forget to use bmw coolant (blue).

[turbo_911]

Oh that's news to me, I didn't know that BMW coolant is Blue. All other cars I've had, the coolant was green so I though ok that's coolant leaking. I bet if it was blue, I would be like, what's that leaking?

Any difference between normal green and BMW blue coolant?

I wonder if the water pump failed just after less than 5k miles on it? Is that possible?

What else should I check while I'm taking that apart?


EDIT:

Ok I've read online a little and some say mix the BMW coolant with distilled water? Some say use Zerex G-05? Some say green is fine? I'm lost lol

[MMMGP]

Here is what's in the green stuff--Peak 50/50 premix.


This is the OEM stuff--additives like acids and hydroxide. I wonder what the bittering agent tastes like.


And here is the BMW chart for mixing:

[tbaker474]

Mix BMW blue coolant 50/50 with distilled water. The BMW stuff is phosphate free which is a must.

[egebhardt]

BMW coolant is blue......... for a while. The the blue additive falls out of solution after a few months and it then looks green.