Grooves in head and cylinder liner surface

[impaw]

Hello,

The groove on on top of the cylinder liner, and the matching grooves in the head, what are their purpose?
As far as I can tell, the fire ring in the head gasket sits within the groove.

My machinist was wondering if Lancia put a pianostring or something there, back in the days:)


the attached photos were grabbed from the internet

[Brian Long]

Hi Torsten,
Back in my engineering days in the oil and gas industry we used RTJ flanges for high pressure piping. The RTJ stood for 'ring-type joint'. The two flange faces had a flat-bottomed, sloping sided groove in them into which a mating ring was fitted. The seal was effected by the slightly differing groove angles between the ring and the groove faces, not unlike the principle used for cutting valve seat profiles.
I think the grooves in the head and cylinder liner acted in a similar fashion in that the copper face of the gasket 'flowed' somewhat into the groves and thus formed a kind of 'fire ring'.
cheers
Brian   

[impaw]

Hi
Thank you Brian, that makes sense!
Best regards
Torstein

[chriswgawne]

Thats what I have always thought as well......which makes me only fit copper faced head gaskets, not other materials.
Chris

[impaw]

That is interesting Chris.
Copper gaskets still available new, or do you reuse older ones?

[chriswgawne]

I have found it is possible to safely and reliably re-use copper faced head gaskets ON THE SAME SIDE OF THE ENGINE as long as everything else in that area of the engine is ok. And yes, there seem to be new copper gaskets still available.
As an aside I soak the gaskets  in water for 12/24 hours before fitting them to the engine 

[Richard Fridd]

By 'copper faced', does this mean these are not solid copper. Some Flaminia head gaskets which I have are copper externally with a different material sandwiched between. Can these be reused?
 Could the annealing ,if necessary, be explained? In an oven perhaps?

  Richard

[chriswgawne]

The copper faced gaskets I am referring to are the ones which are effectively wrapped in copper and have an inner material. These seem to be still available in Italy from bona fide sellers. I have a couple of new head gaskets in alternative material but I have  avoided using them so far.
Chris

[Richard Fridd]

Does the 'soak in water' restore the gasket specification? The copper / composite?? gaskets which I have are still very malleable and annealing would perhaps not be a good idea. Anyone else know about this?

    Richard

[chriswgawne]

The 'soaking for 24 hrs in water before use" gasket tip came from Brian Collins of Weylock Autos back in the 1970's. He was a good motor engineer so I have continued with his advice. I actually have his 'tool' for cleaning out the grooves in the heads and liners which came from Paul, his son.
As to re-using copper faced Aurelia head gaskets, I have done this several times mainly through necessity either when on a long trip or when I havent had a spare on the shelf.
I have never had a problem with an Aurelia head gasket failure.
Chris

[Dikappa]

Chris,

Do you aneal the gaskets in one way or the other?  I would reckon the copper gets harder when used?