[Grease23]

I haven't found a post specifically on this job on the convertible, though many of the other comments on other vehicles do apply. Having just finished doing it, I thought I'd post a few observations that might help somebody whose has already read and viewed the other resources before doing this for the first time. I am not going to repeat things covered elsewhere which obviously apply, such as drain the cold radiator, take off the plastic under-car shield and so on. I am assuming that, like me, you checked out everything available before doing this.

1. At a minimum, no matter if you pumped out the expansion tank and drained the radiator, you're going to get soaked at least two times with coolant on your arm and shoulder. Expect it and dress appropriately. If you have pets (or very small kids) don't leave standing coolant anywhere because it is strangely attractive to pets and kids (it is supposed to taste sweet, though I have to wonder who established that...) and it can be deadly. Remember the secret video tape in The Sixth Sense.

2. The E93 has some chassis braces that are a very minor additional step. These point toward the front of the car, and are held in with three big bolts each. On the right one, loosen the back bolt, remove the one in the middle and front, and then swing the brace counter-clockwise and out of the way counter-clockwise. The left one can be left alone. To access that back bolt you'll have to remove some of the felt under-car insulation on the right. These fasteners holding the felt can probably be turned by hand, though they use small torx fasteners instead of the 8mm ones holding on the big plastic shield.

3. Once you loosen the bracket for the power steering hose, and drop the sway bar, it may still look like this is going to be really hard to do. There is just so little space and perhaps you have very large hands like me. It isn't easy, but it can be done, and loosening/removing things in a particular order helps a lot. Though it doesn't necessarily seem obvious from your position under the car, taking the fan out will make all the difference in the world. On the N51, on the right side of the radiator, there is a small block (ozone sensor?) with some rather delicate wires attached to it, so undo those. There is a spongy plastic baffle that fits a crescent cut out on the edge of the fan frame and that is how the wires reach the sensor. On assembly, position that baffle in the slots before you reinstall the fan. The fan slides into a slot on the right side about half way down, and there is a different kind of slot on the left side that requires you to depress a tab. Top right there is a single torx screw holding it on. And you have to undo another torx screw holding the silver cooler to the bottom left rear of the radiator. The big electrical connector at the top of the fan is obvious, and the wire can be tucked out of the way after it is removed from the fan.

4. This is a good time to replace the fragile overflow tube that goes across the top of the radiator since many people report it cracks and leaks. Be very careful removing the crimped-on connector to the upper (big) radiator hose. I thought I was being careful, but the plastic fitting snapped off the rigid part of the hose. To my amazement (given that the car is not ancient and the part fits many applications) two dealers did not have the upper hose in stock. (I've never seen a dealership that leaves the parts counter unmanned and which lacks a door back into the parts room. That tells me there isn't much need for the parts guy/gal to go back to grab an in-stock part when a customer wants one.) If you replace the upper hose, it is easy to forget to put the third (small, bottom) hose back on. At least it was easy for me to forget that.

5. Most of the DIY videos I've watched are a bit vague and conclusory on exactly how to remove things. The thermostat must be removed before the coolant pump. Yes, it looks easy to get the pump itself out, but reaching the third (top) aluminum bolt looked impossible to me with the thermostat blocking it. The two little bolts holding the thermostat to the pump are obvious and easy. Even with those gone it doesn't move much, unfortunately.

6. The thermostat reminds me of the Jarvic-7, though apparently it is more reliable. Of the four portals to the thermostat, two face more or less to the rear and two to the front. I started at the back. The big one (connected to the hairpin turn U-shaped hose) came off easily due to the accessible rotation of the worm-drive clamp. Note that the U-hose is not as symmetrical as it appears on line -- one end is a little longer. Remember that. At least on my car, the other (smaller) clamp up higher was a real bitch, as the factory installed it with the clamp rotated to the worst possible position for removal. I couldn't access it with 1/4" drives and swivels and had to use a stubby screw driver, turning it slightly before the blade inevitably slipped out of the slot on the screw over and over. My big hands were not an asset. I'm embarrassed to say removing this clamp took me almost a frustrating hour.

7. On the front of the thermostat you don't have conventional hose clamps, you have those locking kind with the wire clips. In this very limited space, flipping up the locking clips with screwdrivers and pulling them off is fairly easy. Lift up the locking tab on the electrical connector to the thermostat with a very small screwdriver and carefully unplug it. The contacts inside look really fragile to me. (Reinstall it slowly and straight on the new thermostat) You can now remove the thermostat -- it will come out easily from the front, but you can finagle it out the back too, though it is more of a challenge from the back/rear.

8. On removing (and installing) the pump itself, the two bottom aluminum bolts are obvious and easy. New bolts are in the box with your new pump.
The top one is hard to see, even with the thermostat removed. Take a look at your new pump so you know where that third bolt is located; you may have to remove it by feel. If the hairpin hose is really stuck on the pump, you can lift an edge with a 90 degree pick, pull it out a little, and then it should come off.

9. If you want to replace your entire "Micky Mouse" hose and not just the plastic flange at the top, now is the time to do it. On the lower end it is held on by a conventional hose clamp and with the engine in the car, you'll never have better access than now.

10. Reassembly really is the reverse process. Pump goes in first this time.
I've seen some suggest that you stick you finger in the new pump and push the brown plastic impellor around to make sure it turns, so I did. And it did.

11. Given the 10,000 fasteners involved in putting shields, etc. back in place, it might be worth pressure testing your work before you do that so you are sure everything is tight and you don't have leaks. Pour in coolant until the tank is near-full. If you have the "Astro" brand kit for pressure testing, use the orange adapter (#78210-06) even though the instructions have no recommendation for an adapter for this car. Keep your drain pan you used earlier handy in case coolant starts pouring out somewhere.

12. Running the program for bleeding the system is covered elsewhere. Given how much coolant 'loss' is involved in this process, it probably wouldn't hurt to run it twice.