I purchased my 550i in 2011 pre-owned with 48k miles from a BMW dealer as it appeared to be in excellent condition. Shortly thereafter the water pump failed and since then have had to replace it twice, so I'm on water pump #4, I've also had to replace a leaking expansion tank and the radiator which have also both since failed. Car now has 101k miles on it.

So I started the car this weekend and lo and behold I received the low coolant message yet again so will need to have my indie address the cooling system yet again.

If anyone else has experienced similar chronic cooling system issues with their 550i please let me know. These issues seem to manifest them selves particularly in the cold weather.

Love it when it is running well but am seriously considering dumping it at this point.

Thanks, Ed

 

I had the same issue with my 07 550i, that's why I'm parting it our, tired of putting money into it and still had to add coolant every few hundred of miles, If i were you I would get another one good diagnostic and dump it if you still having issues..

 

Which water pumps were you using? Are you using all OE/OEM parts?

The cooling system is pretty simple, and even though parts fail mechanically (with wear), they don't normally fail that often. If leaks happened that often, I would suggest using OEM parts if you aren't already -- simply for the fit.

Install all parts correctly, especially the gaskets.

Expansion tanks and radiators don't fail often, especially if you've replaced it recently.

 

Low coolant warnings were common for me when the weather dipped low overnight. Replaced reservoir a couple times due to leaks, did the Bimmerfix stent for the xfer pipe, new hoses and now on second water pump. No issues now for 1.5 years. Make sure you're not leaking from the weep hole in the timing cover, the coolant reservoir, any hoses, or worse, from the cover at the rear of the engine. So many possibilities for leaks...

 

I have to agree with JPR, the OEM parts will last a good amount of time. There are plenty of non-OEM water pumps out there.

However, I will disagree with JPR in that the expansion tanks DO fail in these cars. Mine died at 90,000 miles, but there are many other posters on this site who have had them die at earlier and later intervals. Fortunately the expansion tank is a relatively easy and inexpensive repair.

 

at 90K, it's worth it to replace the cooling system as preventive maintenance. The parts are inexpensive, and the labor isn't bad. For me, it's worth the peace of mind -- knowing I won't be left stranded somewhere.

 

Bingo. Did the same around 110k. Well worth the piece of mind.

 

Thanks all, I'm fairly certain my Indie has used OEM parts unless explicitly recommending otherwise. Could be the last straw though depending on the nature of this most recent cooling system issue.

 

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