K-Series - Strange Cyl Head Undercutting

Hi all,
I was hoping for some advice on the following possible? issue.

I have taken the cylinder head off a 2001 Rover 25 (K-Series Engine after I carried out a compression test and found widely differing results between all cylinders.

I checked to see if the head was warped using a straight edge and feeler guages, I found no evidence of any warping.

What I did find however were strange circular undercuts running around two-thirds of the circumference of each cylinder combustion chamber.

The undercuts are about 1 mm thick and .0006" deep. My findings are quite hard to explain, I can sent a clear digital photo of my findings via e-mail to anyone who thinks thay can help.

There is no undercutting towards the inlet side of the cylinder head.

I have changed many head gaskets and have never seen anything like this.

As I have never changed a K-series head can anyone tell me if this is undercutting is:

1)Supposed to be there
2)Should be skimmed out

Any help would be greatly appreciated

Thanks,
Stephen

Hi Stephen,

Sorry I can't be of help but if you attached such a picture to your message it is possible more people could be of help ?

Good luck.

Piccies please.... if possible?

Guys,

Thanks for taking the time to reply to my request for assistance. I did try to upload a picture of the issue but my file was way too big.

Fortunately I have been advised that the "undercutting" I described is actually caused by the firing rings in the gasket vibrating (or moving) - the technical term for this is firing ring fretting.

Thanks,

Stephen

o, well I wouldnt of been any help anyway never heard of that!

Can you e-mail me the pics please, curious to see it.

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