Started changing the water pump and thermostat on my wife's E39. I have learned the following:
- The coolant drain plug in the block is an absolute beast to reach, but once you know the trick it's not too bad.
- Copper slip all mating interfaces (water pump pulley was corroded to the old pump despite being plastic).
- Do the job in the dry, seriously (duh). It was warm and sunny when I started, with forecast light showers. I gave up when I started shivering and found the only dry piece of clothing on me to be half of one of my socks (light showers my arse). Lying in a puddle is not fun or clever.
I have now got to refit everything (including the new bits), but am waiting until it's dry tomorrow. Should be a piece of cake.