US 4,967,458 AGranted

Process for renewing cylinder heads

AssigneeAutomotive Aftermarket Development Corporation

InventorsEugene Rosenberg, Jay Sanders, Raymond English

Life of this patent

Estimating the term…

Loading patent…

Abstract

A process for renewing a cylinder head, preferably a cast aluminum water cooled cylinder head from a used condition to a rebuilt condition suitable for reuse. In a qualifying stage the used cylinder head is stripped of removable parts, inspected, heat treated for cleaning and stress relieving purposes, and then pressure tested to detect leaks through cracks or excessive porosity. If cracks are located, the cylinder head passes through a reconstruction stage wherein cracked areas are removed and replaced by welded material, recontoured and preferably again pressure tested. A cylinder head which did not need reconstruction (or after reconstruction) then passes to the rebuilding stage where it is essentially machined and component parts replaced. Included in the rebuilding stage is a line-boring and surface gasket facing procedure for eliminating the adverse effects of warpage and a vacuum impregnation step to seal the pores of the cylinder head.

Claims10

Dependent claims

A method for renewing a used cast aluminum water coolant cylinder head to a condition suitable for reuse, comprising the steps of:

stripping substantially all removable component parts from the cylinder head,
cleaning the cylinder head,
heating the cylinder head to relieve stresses,
repairing cracks in the cylinder head by removing the material of the cylinder head in the vicinity of the cracks and, using a welding process, adding back new material to replace the removed material,
compensating for warpage of the cylinder head,
impregnating the cylinder head to prevent liquids from leaking through excess porosity thereof, said impregnating step including subjecting the cylinder head to a vacuum to remove air from the pores of the cylinder head, followed by releasing the vacuum, while the cylinder head is covered by the impregnating liquid, to cause the pressure of the air following release of the vacuum to force the resin into the porosity of the cylinder head and
replacing the component parts of the cylinder head which correspond to those parts which were removed, thereby rendering the cylinder head operable for use with a cylinder block.

4 more elements

Dependencies are inferred from the claim text.