[IndyDave]

After reading the official BMW instructions, the tips in this thread, and a couple of useful YouTube videos, I decided to tackle this project myself. I was a professional mechanic at a Mazda dealership a million years ago (the mid-80’s), so I have decent (if rusty) wrenching skills.

Folks, this project is no fun whatsoever. The first problem I encountered was getting the fan separated from the transmission cooler. As others have pointed out, there’s only one hex screw securing it, but after removing it, the cooler remained firmly attached. The description that the cooler is “clipped” to the fan cowl isn’t quite accurate. The cooler has a tab that slides UP into the fan cowl, so after you remove the screw, you must push the top of the cooler bracket back far enough to pull the fan cowl up and away from the cooler. It took me well over an hour to figure this out and get the fan out of the car. Once that is done, all of the work has to be done from the bottom.

I did not remove the air charge cooler, although I did remove the bottom bracket because my arm kept hitting it as I tried to remove the hoses.

Removing the hoses is very challenging. It’s like trying to do a jigsaw puzzle in the dark using chopsticks. And part of the time, one of your chopsticks is missing. It’s very difficult to get light in the work area, and it’s tough to get your hands and tools to the hose clamps. I used a 1/4” drive ratchet with a u-joint for some of the clamps and a flexible extension for others. I found that it was easiest to remove the back hose from the pump last, after removing the mounting bolts so the pump could be pulled forward a bit, allowing easier access to that clamp. Getting the bolts out of the pump isn’t too tough. I used 3/8” ratchet, extensions, and a U-Joint at the socket.

The other major difficultly was the large quick-connect coupling to thermostat. Removing the clip wasn’t too difficult, but the hose refused to release from the thermostat. You can’t get a good grip from the top or bottom to apply force at the correct angle. I just wiggled, twisted and pulled at it until it finally let go. This step took at least an hour and a tremendous amount of swearing.

Other things to know:
BMW provides no way to drain the coolant without making a huge mess, so you’re going to get coolant EVERYWHERE. Buy a large bag of oil dry before you start.

Make sure you get the large quick-connect coupling fully connected to thermostat housing. This means ensuring that you hear it firmly “click” into place when it’s seated. If you don’t, you’ll get to buy another gallon of BMW coolant and get another round of practice removing the fan and bottom cover.

This job would be much easier on a lift. It’s very difficult to get your arms/hands into the work area while lying on your back. It’s also hard to do the “top” work with the car on ramps. You’ll need something to stand on that won’t slip when you’re leaning into the engine compartment.

If you have any questions, please ask them before I repress the traumatic memories of this project.