Need help finding an M50 coolant leak

[Unregistered]

I changed the water pump and thermostat on my '95 e34 (M50TU engine) and now have a slow coolant leak somewhere in the front of my engine. It is not clear where the coolant is leaking from but it somehow gets on the engine pulleys and then sprays little drips on various components. What are the likely culprits? The leak is pretty slow (the resevoir drops about 1 notch per 500 miles) so I am thinking of just topping it off every oil change. Could this cause problems?

I already changed the thermostat seals a second time and am starting to suspect the water pump. Can the water pump weep hole be inspected while installed? Any ideas would be appreciated.

[JR'Z 525]

When you figure it out let me know. My 92 M50 is doing the exact same thing, even after a new pump and two t-stat o-ring jobs. I get little dried spray drops on the side of the air box and alternator duct. Seems to decrease when the cold level drops 3/8 inch in reservior. I just check it twice a week, watch the temp gauges, and keep my fingers crossed it's not a head gasket slowly letting go...
JR

[AllanS]

I would check the seals around the bottom of the expansion tank. It's dark down there and it can be very difficult to detect- shine a flashlight down while the engine is running normally, and you should be able to see a small line of coolant seeping from the corner.