Coolent leak

[Herb]

Coolent - I have a coolent leak, but have no idea were at. Symptoms: If I wait about 2wks the resivoir will go from alittle over the cold line to empty (I usually add some every 3-4days to be safe) but sometimes it takes longer or less time (wthf), all the hoses are new, rad. is new, thermastat is new (all abou 1 yo). When I turn on the heater I smell coolent, the higher the temp. the stronger the smell, but no wet carpet or any signs of fluid. Exhaust smell and looks normal, nothing obvious.

Thanks
Herbert

[DaveVoorhis]

Your heater core, or the o-rings on the coolant pipes where they enter the heater core, or both, are leaking. The leak isn't bad enough to soak the carpet -- it's still at the point where the coolant mostly evaporates into the air, or pools in the heater box and dries out over night.

You'll need to tear down the center console and pull the radio, heater controls, and OBC (if you've got one) and associated panel to get at it.. It's not a difficult job, but it's tedious. Budget a long afternoon or two for undoing and re-installing a zillion little interior fasteners.

[Ferret]

When I turn on the heater I smell coolent, the higher the temp. the stronger the smell, but no wet carpet or any signs of fluid.

Sounds like your heater matrix has gone ****-up!

Absoloute swine to change too, iirc you have to pull most of the dash apart to get at it!

[Herb]

Sucks.

[Scott C]

Sucks.

Yes, but it is a doable job... And I bet is a possibly more pleasant than replacing the head gasket

[Ferret]

Yes, but it is a doable job... And I bet is a possibly more pleasant than replacing the head gasket

:P HG on a 525i is easy!

[Herb]

I'll have time this week to knock it out, hopefully the weather holds out and continues to be beautiful. Anything else I should do while I'm in there besides the cabin filter.
Thanks all,
Herbert

[Jehu]

Don't fudge on that metal clasp that flips down over the side pipes.Make sure that seats and bolts in properly and fully tighten it. It was difficult on my 540 to position a wrench over there and get that fastener down into its slot,difficult as in took me 1/1/2 hrs to finally get it but i've had the car running a few weeks now and everything has held up without leaking again . Took me about 8 hrs over two days and i was unable to refit all the little metal clips on the air box cover but got as many as i could reach and it seems to be enough in that i feel no loss of air pressure or range of temperatures from heat or a/c which i'd expect if the box was leaking.

[Herb]

Thanks everyone.