In Reply to: E34 535i: Coolant leak from rear of head...gasket? posted by Brock Fraser on March 31, 2000 at 20:41:52:
I also had this fault on my 520. On inspection it turned out to be a head bolt that had partially parted/broken. It actually looked as though a small hacksaw cut had been put into it on either side about an inch or so from the end of the threads. This released the tension on the bolt and the head then leaked. Skimmed, valves lapped and new gaskets & head bolts seems to have cured the problem.
: Got a problem, guys. My car has been consuming coolant for some time now, but at least a portion of it was falling to the ground, so I thought it was just a slow leak. Well, today, the slow leak turned into a fast spew. After letting the car cool, I filled it back up with coolant, drove it up on ramps, and watched where the leak came from once it got back up to temp. The coolant is escaping from the rear of head, but I really can't see it directly even with an inspection mirror. I can see, however, a trail that is either originating from the head gasket, or simply making contact with the gasket on it's trail downward. There is evidence of a bit of froth on the underside of the oil filler cap, and just a touch on the dipstick as well. I drained the oil, to see if coolant was visibly present, but it was not. We have an oil analysis place here in town, so I'm going to get it analyzed on Monday. I obviously suspect the head gasket, since I can't see any other tubes or hoses in the vicinity that would be causing the leak... but then again I would hate to pull the head only to learn that it was something small and stupid. Regardless of what it is, I can't even see it, so working on it would require some major dissasembly.
: I was hoping someone else had seen this and could lend some experience.