They pressurize the system and then check for leaks and they can do it on a lift.Īnyone know how different the 6cyl is from the 4 for the water pump? most of the guides (like the Bavarian one posted here) are for a 6cyl or they don't specify.Īre you saying you have the 28i X3 4 cyl? If so, the part numbers are different than for the 35i and I agree that most, if not all of the info I found is on the 35i.maybe this means good news for the 28i folks in that their water pumps last longer.dunno but here are a few pix from Realoem that show the difference in what the water pump and T-stat look like between the two models. I think the pressure check Wgosma recommended is a good idea and its simple to have done. If I remember, the inside of the belly pan has squares added for stiffness and those can hold a fair amount of fluid before it overflows and you see it on your garage floor - but don't hold me to it cause I may be getting that mixed up with my wife's GTI. Once the roads are dry up here I may do that (probably another 2 to 3 weeks before the snow is gone). Granted I haven't removed the belly pan and left it off, so maybe it is collecting there and then evaporating. It is always parked in the same place in the garage, nothing on the floor. I spent a good half hour with a flashlight and a mirror this morning, and another 20 minutes after a 45 minute drive so it was good and hot. It obviously has a leak that is getting worse, but you are right, I can't see any sign of a leak anywhere. and you're saying that you cannot see any fluid on the floor of your garage, your driveway or anywhere else, like in a parking spot where ever you end up going? and no sign of leaks around any hose ends, clamps, etc, etc, right?

Just trying to figure out how much you've added total. Hmmmm, how long now have you been adding a couple of cups per 2K miles. That much fluid loss should show, shouldn't it? I know the expansion tank is the usual culprit, and that is where I will likely start, but there are no signs of a leak at all. Exhaust is normal, no sweet smell or excess white 'smoke'. I just changed the oil and no milkyness there. The bottom of the expansion tank is spotless, same with every fitting I can get to. I have looked everywhere I can think in the engine bay, with a flashlight and mirror in hand (I washed out the engine bay really well a couple months ago to help find it after a fruitless search at that time as well) No sign of leaks anywhere. Nearly all my driving is city, and it never gets hot (it has been below freezing for the last 6 months up here), but I do have a heated garage that it is parked in every night. Now the warning comes on and I add about 1 to 2 cups of fluid every 2000 ish miles. It is losing far more coolant than it should. I have a 2015 x3 28i, 60,000 miles on the clock.

Bmw leaking coolant