[Groucho]

Do fifties Pontiac V8s oil the rocker arms through the push rods like 60s Pontiac V 8s? Thx

[Bill Hanlon]

Early Pontiac V8s pumped oil up the pushrods to lubricate the pushrod to rocker arm interface. THERE WAS NO HOLE IN THE ROCKER ARM TO LET THIS OIL CONTINUE THROUGH AND LUBE THE ROCKER ARM TO BALL AND ROCKER ARM TO VALVE INTERFACE. To lubricate the rocker arm to ball and valve interface oil was metered through the #2 cam bearing (passenger's side oiling) and #4 cam bearing (driver's side oiling). There is a good explanation of how this worked in the '57 GMC Maintenance Manual (GMC used Pontiac V8s during this period. Look here: http://chevy.oldcarmanualproject.com...5559mm435.html

What is "early" Pontiac? Certainly 1955 through ALL 1960 engines. Somewhere around 1961/2 certain high performance engines started using rockers with oil holes. I think that some Pontiac V8s continued to use the original oiling scheme into 1964.

[tom s]

63 421 HO was the first passenger car Pontiac to use the pushrod oiling I believe.Earlier SD heads got them.Tom

[Bill Hanlon]

The parts marked with the red asterisks are all oiled through the rocker studs.