(MLS) Head Gaskets - Howard Enterprises

TECH TIP
MULTI-LAYER STEEL (MLS) HEAD GASKETS
TOP
traditional
composite
gasket
Layer 1
Layer 2
BOTTOM
a multi-layer
steel (MLS)
gasket
5 layers shown
Layer 3
Layer 4
Layer 5
application) of heat treated stainless steel. Each layer is separated by thin layers of a nitrile
rubber coating. They have also been embossed in key areas to aid the sealing process, and
maintain proper sealing forces between the head and block.
The correct surface finish requirements on both the cylinder head and block are very
important to maintaining a proper seal when using an MLS head gasket. Most manufacturers
call for a 40 Ra or less. Check with your gasket or engine manufacturer.
If you are switching from a traditional composite head gasket to an MLS head gasket, both
the block and head will most likely need to be resurfaced to achieve the finish required.
Some of the old resurfacing machines just cannot achieve this fine of a finish.
**DO NOT SPRAY, OR APPLY ANY COATINGS TO MLS HEAD GASKETS THAT
HAVE A COATING FROM THE MANUFACTURER.**
The surfaces on these gaskets that contact the cylinder head and the block are coated with
a special nitrile material designed to seal not only compression from the cylinders, but also
the water ports. Any added coatings can cause the gasket to move around more than
designed, causing leaks.
Contact Scott at 800-880-2527 or [email protected] for more information!