I have a 07 550i and the alternator and thermostat are going. I plan on doing it myself. I read some instructions from the TIS on how to change the alternator and it says I have to remove the fan and radiator. Has anyone ever done this, do I have to remove the radiator and fan? I took a look at it and it seems like a tight squeeze.

 

You do NOT need to remove the radiator. You WILL need to remove the fan. Use a thin sheet of wood or cardboard fitted against the radiator while working between the engine and radiator to protect the thin fins on the radiator.

And unless you have replaced them recently, when you have the car apart you will also want to consider replacing the water pump, hoses, belts, vent tube and coolant reservoir, all items that tend to fail in the 70K-80K mile range. Plan on replacing the bolts in the harmonic balancer (removed if you replace the water pump) as they are aluminum and are designed to stretch. Don’t drop the harmonic balancer once off the car as it is very pricey.

TIP: While the alternator is not that heavy, supporting it while bent over the car trying to shoehorn it out, and the new one in can be fatiguing, and there are times when connecting and disconnecting cables at the rear of the alternator that you will need two hands. Set up a cardboard box between the engine and radiator that will sit 1/2” to 1” below the level of the alternator. When you unbolt the alternator the box can be used to support the alternator while you are working on it.

Also be careful to have the alternator fully seated and square against the alternator bracket and finger tighten the bolts before putting a wrench to them as they are easily stripped. If you don’t get the alternator square against the bracket the pulley will not align true with the other pulleys, and tensioner and you will eat belts quickly. And try not to put excess force on the alternator bracket, as underneath it sits a profile gasket that is one of the truly horrible repair jobs on the 8 cylinder engines (along with the water pipe and starter).

 

Really appreciate the advise. I was planning on going from underneath, I have access to a professional garage so I was planning on using a lift and go from underneath. Kinda scared though sounds like a lot of work. I am also doing the thermostat at the same time.

 

Just the thermostat and not the waterpump? How many miles on the water pump? Experience shows the average water pump failure on the eight cylinders is between 70K and 80K miles. They are not that expensive and much cheaper than the cost of overheating the engine, towing, potentially being stranded out of town, etc. IMHO you would only be delaying an inevitable overheating episode by doing only the thermostat. You are doing all of that work to take parts off the engine to get to the alternator. Only a little more work will take car of the preventive maintenance on the water pump. And the belts are already off and they are cheap to replace.

The alternator cannot be removed working from below as there are hard lines blocking access (transmission fluid cooling, etc.).

When I replaced my alternator I used a brand new OE unit as I am not a big fan of the spotty reliability of rebuilt alternators. Below is the best price I have found.

BMW*650*Alternator from CarPartsWarehouse

 

You are right, I will replace the water pump as well. The car is coming up on 80K, not sure if it was replaced before, I am the second owner. The pulleys are kinda loud so I am changing everything, belt pulleys, pre-tensioner. I am gonna go with an auto-zone alternator to keep down the cost, I am gonna let the car go within the next year.

I remember reading somewhere that there was a water pump with plastic parts and one with aluminum parts, do you have any ideas or source on that?

 

If you're not sure whether you will trade the car or sell it to a private party save all of your receipts as any potential private buyer will be impressed with the preventive maintenance.

Pelican Parts has several units with metal impellers at a good price.

BMW E60 - Water Pumps & Hoses - Page 2

 

I need your help. I tried to do the replacement today but I got stuck at the fan. I could not remove the fan cowling, it seems the AC condensor is attached to it. I've attached a few pictures to show what it looks like. I read the BMW TIS and it says just pull the fan up after releasing five screws on the radiator cover. Can't do that when it's connected to a bunch of hoses and pipes. Also the power steering hydraulic lines seems to be in the way how dd you get past those?

 

Sounds like you have removed the screws and disconnected the electrical connectors.

There is a tab on drivers side edge of the plastic fan housing (about even with the center of the fan itself) that folds in, allowing the fan to then be lifted straight up.

It will take a little wiggling, but the fan will clear all of the hoses and pipes.

You may be mistaking the plastic brackets that hold the fan itself as being part of it, but there are no hoses or pipes connected to the fan housing.

 

I'm doing my water pump today and I'm stuck at the same spot. No cooling fan diys show the hoses that are connected to my fan shroud. I figure these are cooling lines for the active steering or dynamic drive? I removed the top driver side hose but I can't get a driver side lower hose to budge. Hell, there's no insigne as to what these hoses even connect to! It's an electric fan so I'm a little perplexed as to the oil coming out of the one hose. No amount of wiggling is gonna get this fan out. Help, someone!

 

If the 550 is the same as the 545 there are no hoses connected to the fan housing. Why would there by, it is just an electric fan.

The only extra lines I can think of that the 550 has over the 545 is I believe the 550 has an oil cooler, but those lines go into the radiator under the fan, not into the fan.

Look at the the diagrams on realoem and google the fan itself on parts web sites to see what it looks like out of the car, which should help in knowing what to pull and tug on.