I am looking to replace the water pump on a E34 540i. I was wondering if anyone could tell me how involved this procedure is (time, special tools, difficulty). I do have some experience with maintenance on Japanese and American cars. However, I have heard horror stories about DIY maintenance on German vehicles. I am hoping to get this done in a very short time as I already have the pump on order and I have to take a 1000 mile road trip in 5 days and I would feel much better about doing it without a coolant leak. Right now, the leak is very slow. Approximately 1 drop every 5 seconds. I can't tell where the leak is coming from on the pump (from the shaft, around gasket, etc.) Any help with this subject would be greatly appreciated.

Thanks in advance,

Brad

Use a screwdriver to hold the water pump pulley while you wrench the big nut that is a reverse thread. If you loose grip on the hex bolts get some allen head bolts to replace the others it will give you more grip on the pulley. Order a metal thermostat housing because the plastic one WILL leak. Great time to replace the thermostat. I think these engines dont like cheap coolant, mix 50/50. Get a six pack or a case of 12 (it attract helpers). I had to temove the aluminium elbow with the ASC system to clear the way. May be a great time to change the belt too. Put a peice of cardboard in front of the rad to avoid drama.
Have fun.

Use a screwdriver to hold the water pump pulley while you wrench the big nut that is a reverse thread. If you loose grip on the hex bolts get some allen head bolts to replace the others it will give you more grip on the pulley. Order a metal thermostat housing because the plastic one WILL leak. Great time to replace the thermostat. I think these engines dont like cheap coolant, mix 50/50. Get a six pack or a case of 12 (it attract helpers). I had to temove the aluminium elbow with the ASC system to clear the way. May be a great time to change the belt too. Put a peice of cardboard in front of the rad to avoid drama.
Have fun.

+732475234659876239476972854

I just went did all this with my 530i and it was a lot of fun :)

As stated above if you don't have the special pulley holding tool, you will need to have a helper jam a long stout screwdriver between the pulley's bolt-heads, while you use the 32mm wrench (from a bicycle shop) to turn the fan nut clockwise (left-hand thread). After that it's pretty staraight forward. Just remember that there are two coolant transfer tubes running from the water pump to the back of the engine. These use o-rings on each end. Your local dealer has them and they're cheap. Look up the drawings on "real oem.com", group = engine, subgroup = engine cooling. I'd post a link but I don't have "permission". Buncha BS.


Regards,
M.R.