How to Replace the Valve Cover Gaskets on a Ford 351by John Stevens
Ford first equipped its vehicles with the 351 eight-cylinder engine in 1969. Ford considered the 351 necessary to compete with General Motors' 350 engine. In creating the 351, Ford essentially used the earlier 302 engine and lengthened the piston's stroke. The 351 featured a pair of one-piece valve cover gaskets to conceal the rocker arms. Oil circulates underneath the valve covers to lubricate the valve train. It is for this reason that a damaged valve cover gasket usually results in an oil leak. Replacing the 351's valve cover gaskets usually takes less than an hour.
Allow the engine to cool to avoid skin burns from hot valve covers.
Pull the breather cap off the top of the valve cover.
Remove the six bolts that secure the valve cover to the top of the cylinder head with a socket wrench and a socket extension.
Lift the valve cover off the cylinder head.
Turn the valve cover upside down, then peel the old gasket off the outer edge of the valve cover.
Apply a coat of water-resistant sealer to both sides of a replacement gasket, then position the gasket onto the outer edge of the valve cover. Ensure that the gasket's bolt holes align with the valve cover's bolt holes.
Position the valve cover onto the top of the cylinder head, ensuring that the valve cover's bolt holes align with the bolt holes on the cylinder head.
Insert each of the valve cover's six retaining bolts through the edge of the valve cover and into the cylinder head, then tighten the bolts only until they are snug, to avoid damaging the gasket.
Press the breather cap into the opening on the top of the valve cover.