Assembly consisting of a seal gasket for valve stems and a spring support cap

Claim 2

In combination with the cylinder head of an internal combustion engine having a valve and valve guide extending through the head and a coil compression spring acting between the valve and the cylinder head, a gasket surrounding the valve guide and sealing against the valve stem, the gasket having a radially outwardly extending flange on its end adjacent the cylinder head, and a spring support cap surrounding the gasket and having an interference fit with the gasket and resting on the cylinder head, the valve spring pressing the support cap against the cylinder head, the support cap having an annular recess in which said gasket flange is disposed.

Claim 3

An assembly as claimed in claim 1, said support cap having a radially outwardly extending annular flange that rests on the engine cylinder head, said spring acting between the valve and said support cap flange.

Claim 4

An assembly as claimed in claim 1, wherein the cap comprises more than one spring support base, these bases being of different diameters and each being separated from its adjacent base by a step.

Claim 5

An assembly as claimed in claim 1, wherein the bent lateral edges of the gasket are retained against the cylinder head by the cap which rests on them.

Claim 6

An assembly as claimed in claim 1, wherein the gasket is constituted only by a material having the following composition: ______________________________________ QUANTITY ______________________________________ ELASTOMER Acrylic ethylene copolymer 350-480 Acrylic butadiene nitrile copolymer 40-60 FILLERS Silicic acid 60-80 Aluminium and magnesium silicate 340-460 Polymer plasticiser 15-25 ADDITIVES Chromium oxide 5-10 Stearic acid 10-15 2,5-dimethyl-2,5-(1-butylperoxy)-hexane 10-15 4,4-butylidene-bis-(6-tert.butyl-m-cresol) 5-15 ______________________________________