’89-’98 fire ring gasket, .070″ thickness , 4.560″ wire O.D.
1.5mm gasket, radiused grooves should be .013” in the block and head or .025”-.026” if only using one groove in either the head or block
For best results please have your head and block machined prior to installation for flatness. For engines under 800hp, cutting grooves in the head or block is adequate, but for higher horsepower engines we suggest cutting grooves in both the head and block. We suggest a radiused cutter for all installations. Studs are a must for proper clamp load. Our rings are made from .105” wire and are 4.560” in diameter. When using our competition gasket, studs are a must. Be sure to use a liberal amount of lubrication on the nut, washer and threads of the studs so that every stud sees similar clamp load. If lubrication varies stud to stud, clamp load on gasket will not be equal and can allow gasket failure. Never under any circumstances, should you take a fastener beyond the limits listed by the manufacturer. There is a huge amount of potential energy in fasteners at full torque. We suggest 130 ft/lb of torque for initial startup. Get engine to operating temperature, then retorque while hot. You should check valve lash after each torque sequence as re-torques crush the head gasket more and will make valve lash less. It is always a good idea to re-check torque at least one more time before you take engine to full load/rpm. Thank you for purchasing Hamilton products for your diesel.
