2002 bmw 330ci overheating

Are you bleeding it properly? Check some youtube videos. Engine cold, heater at max 91 degrees and fan on all the way to open the heater core valves. Pour the coolant into the reservoir with the bleed screw off, till the coolant comes out with no bubbles, re install bleed screw and suck some extra coolant till the red stick is flush with the top of the reservoir and recap.

I did that but my resavoir fills up like it's not flowing so I cant pour anymore coolant in.

Does coolant come out the bleed screw? Pour slowly. Sometimes its better to fill the system with the front end in the air. Do you know if anyone in the past used stop leak in the system?

Nothing comes out of the bleed screw. I dont even see any flow. That's what I cant figure out.

How old is the overflow tank, hoses and radiator? Did you try draining the system and refilling measure the amount? Draining the overflow tank and radiator will only net you no more than a gallon worth. When you replace the water pump and thermostat, there isn't much coolant loss as you know. The whole system only uses a little over 2 gallons, block and heater core included.

Coolant will not be flowing through the system, since the engine is off. You pour the coolant into the overflow tank until it comes out the bleeder screw. Make sure the engine is off and the heater on max at 91 degrees and the fan on. The red bobber will be fully out of the tank as your pouring it like the videos. If you are still having issues, I suggest taking it over to a BMW indy shop so they can do some further testing.

The radiator is about a year old. The tank cracked so I just installed a new one and I haven't been able to get it bled since then. The tank also came with a coolant thermostat that I replaced as well. I cant figure out why it's not flowing. I'm able to pour about a half gallon in the tank and that's it. It wont take anymore.

I'd be looking for a cracked head or blown head gasket. Very common on a BMW that's been overheated. Hope that helps! Jim

Then the cooling system must be full if no more than a half gallon goes in. But coolant should come out the bleeder screw. Maybe the upper hose is blocked at that area? If the car gets hot after you drive it, and you check the coolant in the tank, is it low? If yes, then you very well might have a cracked head or blown head gasket like JS mentioned. These engine can not overheat at all, one time is too much in some cases. Most E46 owners will replace the engine vs paying all the labor for a major repair like that. That is why I suggested you visit a mechanic before you start replacing other parts and you still continue to be having an issue. Unless the rest of the car is in fine shape, I would think twice on replacing the engine due to the costs. Good Luck.

Thanks for your help. After talking to you guys and a few more videos I figured out I wasnt bleeding it properly nor adding enough coolant. I did it again this morning and I've been driving it all day with no problems and the heat works now as well!!