2001 325i Overheating

[e46325i]

I bought a 2001 325i a few months ago, and within a couple weeks of buying it, it began leaking coolant. I took it back to the dealership, who told me that there was a crack in the coolant expansion tank, and that they had repaired it. About a week ago, it began leaking again from the expansion tank, so I'm assuming that they didn't fix it properly (it wasn't a BMW dealership). I drove it for around a week, putting coolant/water in every time the light came on, and then got stuck in a bit of traffic and was unable to pull over when it came on. The temperature gauge didn't register any change, so I let it go until I was able to pull over, during which time, the head for the bleed bolt (on the hose that goes between the motor, expansion tank and radiator) broke off. I believe I'm correct in assuming that the bleed bolt also doubles as the pressure release valve? Anyway, I pulled over, let it cool and filled it again, then drove to the parts supply store to pick up the new tank that I had ordered. On the way home, it began overheating. I replaced the tank upon ariving home, and fired it up. It's still overheating. Based on the fact that the heater doesn't put any heat out, I'm assuming that it's either the water pump, the thermastat, or both. After reading several posts regarding the same symptoms on here, on the E36 models the water pump has a plastic impeler. Is that also the case for E46 models? I'm going to re-bleed the cooling system tonight to make certain that all air is out of the system, but am pretty certain that that is not the problem. Any ideas or advice would be appreciated. Thanks!

[e46325i]

Originally Posted by e46325i

I bought a 2001 325i a few months ago, and within a couple weeks of buying it, it began leaking coolant. I took it back to the dealership, who told me that there was a crack in the coolant expansion tank, and that they had repaired it. About a week ago, it began leaking again from the expansion tank, so I'm assuming that they didn't fix it properly (it wasn't a BMW dealership). I drove it for around a week, putting coolant/water in every time the light came on, and then got stuck in a bit of traffic and was unable to pull over when it came on. The temperature gauge didn't register any change, so I let it go until I was able to pull over, during which time, the head for the bleed bolt (on the hose that goes between the motor, expansion tank and radiator) broke off. I believe I'm correct in assuming that the bleed bolt also doubles as the pressure release valve? Anyway, I pulled over, let it cool and filled it again, then drove to the parts supply store to pick up the new tank that I had ordered. On the way home, it began overheating. I replaced the tank upon ariving home, and fired it up. It's still overheating. Based on the fact that the heater doesn't put any heat out, I'm assuming that it's either the water pump, the thermastat, or both. After reading several posts regarding the same symptoms on here, on the E36 models the water pump has a plastic impeler. Is that also the case for E46 models? I'm going to re-bleed the cooling system tonight to make certain that all air is out of the system, but am pretty certain that that is not the problem. Any ideas or advice would be appreciated. Thanks!

Coolant isn't circulating beyond the water pump, so I found my solution. Thanks, anyway!