Head gasket failure
 

I have a CSL here with a blown head gasket. Caught this one very early, you can see it's only gone through 1 layer of the head gasket. I've never seen one like this before, it's usually gone through all 3 layers.

Smooth running values were perfect, only a cylinder leakage test showed an issue. a leakage of 12%-14% was measured, with the leaking air heard and felt down the spark plug hole of the adjoining cylinder.

Given we've caught this early I'm hopeful there won't be any issues with the big end shells. The block and head are also still in perfect condition.

Thanks for the post. I am wondering how many miles on that car?

Im thinking i'd need to get a leakdown test done aswell :bigcry:

Looks like you've caught this just in time, nice easy job, Csl so easy to work on, I've been working on my Nissan d40 this week, snapped timing chain, and bent a couple of valves major stripdown, fookin nightmare to do, :bigcry:

Good find.

I will get mine checked on next inspection.:smokin:

64k on this one. Done them as early as 47k, but somewhere between 70-100k seems to be the norm. A lot of S54 engines seem to be fine after that too, no real way of telling.

Worth an hours labour to get it checked in my opinion:thumbs:

A much more familair sight, with a complete failure of the head gasket. Always seems to be between cylinder 1 & 2, and 5 & 6 that go first. You can see the effect this failure has on the block, with a heavy heat build up on the bore in the area of the failure.

This engine cleaned up perfectly and measured up fine, so just a new gasket for this one.

James, is there some point where it's worth changing the HG anyway, as preventative maintenance ?

You did the leakdown test on mine last year, and it was fine, but I suppose they can fail at any time.

Id say 60k miles

Dificult to say really, although 60k is a good starting point.

Certainly worth doing relatively regular (yearly/bi yearly) cylinder leakage tests for piece of mind (depending on your annual mileage), The results of that would determine whether or not the head gasket is failing.

For ultimate piece of mind a replacement is the only way. For owners runnng BMW warranty the head gasket is covered, as is any consequential damage caused by a failed gasket.

Having a read through old posts,,had a thought on this m problem,,Could this be caused by slight bowing of the deck or head over time, as these blocks are so narrow between cylinder bores , with no bolts between bores,,and allowing this to happen, perhaps not got the full clamping force to gasket. , “”” just a thought”