[tjlees]

https://www.bbc.co.uk/news/uk-england-cumbria-64471386

That the N57 engine had flaws first became apparent nine years ago. Then, in January 2016, came the first "thermal incident" - a police car fire caused by the same crankshaft bearing issue that later affected PC Dumphreys' car.

BMW UK reported what was happening to its German parent company BMW AG. Tests showed engine oil was being degraded by high levels of idling - sitting, parked, with the engine running. This reduced the oil's lubrication, leading to wear on the engine's crankshaft bearings.

Hmmm ... risk of thermal incident and death then ...

[mmm-five]

Seems like a screw up at a lot of levels.

• Due to the unique method of use in the UK...that no other police force in the Europe follows
• BMW not simply recalling / replacing these cars
• Police fleet managers not taking them out of service
• Police fleet managers deciding to not follow, nor ensuring their garages/technicians were following, the directives from BMW as they wanted to save money and keep cars on the road

No 'confirmed' cases of it happening to consumer units though.

[tjlees]

15% failure rate though, if you leave your vehicle idling for 50% of the time (rather than 30%) - not sure where the ASS fits into this.

The consumer may not have 'confirmed' the fault, but N57 failures are not rare and tend not to cause death - unless you are travelling at 130 when the engine let's go.

I'm not sure if this is just outside the design spec or bad design.

Given my high miles, my CBS has started stretching the service intervals - now 22-23k between oil changes - here they are talking 10k or less service intervals

Anyway of knowing that your N57 is going to let go with a 'thermal incident'?

[F32Fleet]

I have a had time believing these engines catch fire because they seize and window the block.

EGR issues causing a fire, yes BMW had a recall on those in multiple countries but I don't remember if the N57 was part of it.

Seems to me that police departments were cutting corners on maintenance. How expensive could bulk LL04 5w40 be anyways?

[tjlees]

I've only had 2xEGR and airbag recalls on my N57 - nothing on bearings nor CBS mods.

If anything the CBS has stretched out the servicing interval.

Not analysed the oil, but doesn't burn anything between oil changes - however concerned it will suddenly go bang ....

[Soul_Glo]

Sorry to resurrect an old thread. I am trying to make sense of why an engine would catch fire from idling and then being driven hard. I know of emergency service drivers who have had their engines idling all night and responding to another emergency in the morning. Doesn’t add up. Feel free to be as technical as you want. No stranger to spanners.