LJTX545I

My car is a 2005 545i. Changing the water pump this weekend, was hoping to get the alternator out too but it will not come forward. Question I have is on the A/C compressor belt. Notice there is an empty thread for a bolt down at the bottom, where maybe there is supposed to be a tensioner or an idler pulley. Does anyone know if there is supposed to be one here?

Had to remove the drive pulley out to get to one of the bolts for the water pump. Having a hard time reattaching the compressor belt, maybe will need to go out and find me a special tool (or something to fab one out of). Any tips appreciated.

kouichi

healthservices

If it is this one don't worry about it. This motor was used on other vehicles like some Range Rovers too.




The thing you will have to worry about is putting the ac belt back on. Make sure to use the factory contitech type belt so it will stretch properly, You can go to the dealer and pay as much as $45 or go online and still get the same correct belt for as low as $8

LJTX545I

thanks! I have the contech belt. 4PK 824. Got it from Mr. Romani at Newport.

Here are some notes from my work so far.

1) I ordered the pump from RM European. it comes with O-Ring and seal gasket. You also need to order a water pipe, As precaution I also replaced the thermostat and the temp/oil sensor.
2) I had replaced the lower radiator hose before, I am going to go ahead and replace the other radiator hoses.
3) You can do this without taking off the cooling fan, but that will give you more room for your hands and tools.
4) I removed the heat exchanger for the transmission oil, only because I wanted to take out the alternator. Unfortunately, Momentum BMW sold me the wrong O-ring.
5) Getting the water pipe aligned properly is the key to getting a good fit on the pump

e6t.lab.rat

We have the same vehicle, same year too and I replaced my waterpump 4 mo. ago. Yes, that threaded hole is for a tensioner but, you really don't need one. You could add one if you'd like but most of our cars didn't come with one. I think the earlier models had them in place.

You're going to need a 27mm socket with a breaker bar to turn the crank (clockwise) to re-attach the compressor belt. Don't waste your time trying to slip/spin it on with a screwdriver, it's nearly impossible. I wasted nearly an hour trying duh. Embarrasing to say this now but it took me no more then ten seconds with the correct tools. Good luck

turboawd

you definetly need to use an oem belt. i tried a aftermarket belt and it just wouldnt stretch enough, and snapped it.

i took a breaker bar and socket, and used that to slowly turn the motor(via crankshaft pulley bolt, while i "walked" the ac belt back on.

meatzorb

I have an '04 545i with 115K miles. What were your water pump symptoms that led to replacement? Was it proactive. leaking or noisy? Also, did the pump have metal or plastic impellor? I know not the same pump as on the 3.0 and 2.8s but the impellor seems to be the failing point.

LJTX545I

Actually, it was leaking coolant from the gasket behind the pump that forced me to take off the pump. The pump was still working, and the inside of the old pump looks clean. I will post pictures later. I believe the impeller is made of some light alloy, maybe an anodized aluminum. I think I could have just changed the gasket and it would have been good for another year or two but I went ahead and replaced the pump, thermostat, water pump pulley and most hoses as well. Before this I was having alternator problems, I wonder now if this was being caused by this leak from the pump.

dawid_w

Hi,
What kind of alternator problems do you have? I replaced my alternator a month ago. It is not that hard to do.
I also replaced the water pump and the valley pan (it was leaking bad). I have 97k miles on my car (05 545i).

Do you have any leaks from valve cover gasket? In my case - valve cover was leaking directly on the alternator.
I replaced the valve cover gasket too - this job was very time consuming.

dawid_w

Where did you buy the special tool? I used 2x small screwdrivers and was able to put it in. I was a major pain!!! ;-)

healthservices

You must not have active steering, had a friend to help, or totally moved it out of the way. The tool is $145 thru my dealer but I had to order it. so I made my own for $5 (took two minutes to make) with the help of a hack saw. Then it took only a couple seconds to put the belt on.