Coolant leak on e46 318i 2004

[djdasantha]

Hi Friends,

I have coolant leak on my e46 318i. I know there are loads of threads regarding coolant matter in this forum and other forums too. But I did not get what I want yet. Hope you guys will help me out. I did not replace expansion tank yet. I just need to confirm the actual cause of the issue. Whether it is Expansion tank or Radiator or any other thing. I have uploaded the picture of leak point (Red Arrow). Hope you guys point out the actual cause by looking at the pic.
Thank you very much for your time.

[charter21p5]

Is that the exact source of the leak?

[djdasantha]

Is that the exact source of the leak?

Thanks for the quick reply charter21p5. Yes this is the exact point of the leak. The coolant is leaking through the metal and black plastic parts.

[MIKYZZ4]

Have a cooling system pressure test done to indicate location of leaks. It is very difficult to give a reliable diagnosis from that photo, as the expansion tank is directly beside the radiator. Fluid has a habit of migrating from here to there.

[chasebur]

Did you figure out what the problem was, I have the same issue?

[MIKYZZ4]

#1 culprit is commonly the expansion tank, check it for cracks. The system is usually refreshed as a whole, since the system consists of plastic parts that age and crack in unison.

[TonyAngel]

If one component is leaking, the rest will likely go more sooner than later. Unless you have a reason to, don't replace the cooling system in pieces. Just do the whole thing. Water pump, thermostat, expansion tank, radiator, pulleys and associated hardware.

[chasebur]

If one component is leaking, the rest will likely go more sooner than later. Unless you have a reason to, don't replace the cooling system in pieces. Just do the whole thing. Water pump, thermostat, expansion tank, radiator, pulleys and associated hardware.

Thanks, I replaced the auto transmission thermometer, expansion tank, upper radiator hose,and the radiator adjustment screw and plug. I still am getting this leak. I am getting it looked at by a family mechanic wednesday. I most likely will end up replacing the rest as well.

[Leothelion092]

Thanks, I replaced the auto transmission thermometer, expansion tank, upper radiator hose,and the radiator adjustment screw and plug. I still am getting this leak. I am getting it looked at by a family mechanic wednesday. I most likely will end up replacing the rest as well.

If you've replaced expansion tank only thing left to replace from there is the radiator or the thing the expansion tank rests in (I forgot what it's called lol)

[chasebur]

If it helps anyone, it was my radiator leaking near where it connects to the upper radiator hose. At first i couldn't see the leak, but after putting a paper towel beneath where they connect I was able to locate the leak.