5 series radiator problems - BMW Forum

rwl0827 · 11-29-2009, 10:43 AM

I have had two instances where the upper neck of the radiator has broken while driving on the highway resulting in loss of all coolant. This happened once with my 1995 540 and again yesterday with my 1993 525. Is this a problem that others have experienced with the 5 series?

marti5 · 11-29-2009, 10:51 AM

Im afraid this is a recurring problem on most series of BMW as they went on the "green" way of doing things and using recycled plastics, bad move!, there are companies that do full aluminium rads...google search should find you one but they are few and far between....You are not alone.

rwl0827 · 11-29-2009, 11:26 AM

Thanks for the quick reply. I've already got a replacement rad on the way but I'll see if I can find the all aluminum for the next occurance. Cheers, Rich.

mingusmcbride1 · 12-02-2009, 04:53 PM

Same thing with my 94 530i. Even better, it happened as I was leaving my 20 yr High School reunion (girlfriend had been idling in the parking lot with the AC on for about 20 minutes in 90 degree weather). Pretty easy replacement though - the radiator not the girlfriend.

yaofeng · 12-03-2009, 11:23 AM

You probably tightened the clamp on the coolant hose too tight. Even if you don't the life of plastic under constant heat up and cooldown won't be forever. On the e39 the hose clamp has been replaced by an o-ring so no hose clamp is used. It still happens.

The pictures below are from the top radiator hose on my '01 540it after 115k miles. The offending connector is on the water pump side.