Serpentine belt diagram for 745i [Archive] - Bimmerfest - BMW Forums

: Serpentine belt diagram for 745i

02-26-2010, 12:51 PM
this morning i hear a bad knocking noise from a pump on the drivers side of the engine. its not coming from the engine its coming from a large pump. its not the ac compressor , alt. water pump or any pullys , its a pump thati have no clue what it is. does anyone have a diagram with these parts so i have some idea what this is going to cost me when i order the part. it has a little 1/2 house coming out of it and it seems to hook into the cooling system. it also has an electrical hook up with 2 wires but the pump is large. what is this thing???\


02-26-2010, 12:56 PM

02-26-2010, 01:01 PM
thanks seven, i tried that site before and it dont show me that pump, its making ne nuts that i cant find out what this pump is and what it does,,, i dont even know how to descibe it lol

02-26-2010, 01:07 PM
all the parts are on that site... so just keep looking

02-26-2010, 01:13 PM
Alternator (it's water-cooled, so contained within a housing). Search the alternator threads on here and you'll find plenty pointing to what you just mentioned. These alternators can be rebuilt at any ol' alternator shop MUCH cheaper than buying a new one, just make sure the voltage regulator's connector faces the right direction when you get it back (there are two similar voltage regulators that can be used on these, but the connectors are shaped differently).

Alternator --> here (
Alternator mounting parts --> here (

02-26-2010, 08:00 PM

04-02-2010, 11:53 AM
It sounds like your describing the Vacuum Pump..... Which is on the passenger side. Did you ever figure this out?

04-02-2010, 12:53 PM