Oil leaking into cooling system

On Wed, 18 Oct 2006 02:32:40 GMT, "moehassan" waffled on about something:

You don't say how many miles you covered in that 3-4 weeks, but given that you've put 92K on in 5 years, I guess it would be quite I bit.

I wish you luck getting BMW to "step up to the plate", 92K miles is not in insignificant mileage, and 5 years old is well outside of the original warranty.

It wasn't long ago that a car reaching 100K was considered good going.

To me $3k for a head gasket and rad is a bit steep though, then again that's the kind of thing I would tackle myself, and I guess parts don't cost as much to get to me in the UK.

Dodgy.

The cheapest diagnosis is loose head bolts, but these were torqued up correctly in the factory, and should not present a problem unless the head has been worked on. NOTE some BMW's have single use head bolts that should not be refitted, in which case you will have to get a complete set of new ones.

The cheaper diagnosis is a head gasket. More expensive are warped head (e.g. after any overheating incident) or a cracked block (e.g. after any freezing incident).

A basic compression test should reveal which cylinders are affected, you may be able to hear the escaped, and once the head is off it can be checked for planeness fairly easily.

The failure you describe, in the order of events you describe, is extremely unusual. The E39 is known for a weak cooling system (although the I6 is less problematic than the V8). Cooling problems (stuck thermostat, radiator failure) that result in overheating can lead to failed head gaskets and/or cracked cylinder heads and the symptoms you describe. This is exacerbated to a degree by the temp gauge that will resolutely stay centered until the temp climbs outside the normal operating range.

What was the most recent service on the car? When was the oil last change? When was Insp II done? Has the coolant been drained and refilled at any time (BMW recommends every 4 years since date of manufacture for your car ... 2 years is better)? Anything unusual in either the car's use or performance prior to the arrival of the first symptom described?

There's a small possibility the engine had a manufacturing defect of significant magnitude that BMW might feel inclined to replace it outside warrantee (flaw in the head or block casting ... good luck!).

With 92k miles on it? Good luck getting BMW to cover anything...