Block and head gasket surface roughness
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1998 E300TD
Block and head gasket surface roughness
Does anyone have any experience in what the roughness average needs to be for the block and head surface?
This is from the Fel-Pro website: OEM MLS gaskets work well on new, flat, clean castings, since they require a very smooth surface finish, usually 20-30 Ra or less.
Cometic recommends around 50Ra for a MLS gasket.
From digging around on some engine building website it seems the smoother the better for MLS gaskets but was looking for any more definitive information.
This is from the Fel-Pro website: OEM MLS gaskets work well on new, flat, clean castings, since they require a very smooth surface finish, usually 20-30 Ra or less.
Cometic recommends around 50Ra for a MLS gasket.
From digging around on some engine building website it seems the smoother the better for MLS gaskets but was looking for any more definitive information.
