More BMW loose internal engine bolt madness

Matt Simis

When I got the 850CSi (2years ago?) I read up on loose Banjo bolts which leads to excessive camshaft wear. I opened it up and found one backing out as expected:



Since then I have added a 1995 540i to the collection that will be made into some sort of track toy. The M60 4litre V8 engines are known for two things: Nikasil problems and loose oil pump bolts. This is an Alusil block so the first isnt a concern, however the second was always playing on my mind. Check out what I found when I removed the oil pan:

Thats 4 bolts and 1 nut that have fallen off the oil pump housing! The oil pan is scored from the bolts rolling about and the oil pickup itself has serious scraping (hmm.. got to worry about metal shavings in the oil):

There are so many bolts out that Ill need to go check where they go back in (and Ill thread lock them).

Here is a video of the oil pump and the chains tension as it sits now:

https://www.youtube.com/watch?v=fjWxKzssDyw

I like to think Ive saved another engine from "planned obsolescence" today!

Voodoomelon

Its incredible that the oil pump bolt problem is common to so many BMW V8s, it must be some kind of resonance or vibration problem. Or under spec'd torque values maybe?

ShiresV2

I don't know if it was mentioned before but on the M50/M52/M54 engines the nut that holds the oil pump sprocket on is known to come off too.