Product Service Letter P-344 April 29, 1957
Crankcase ventilation tube oil leaks. (1957 272 truck and all 57 car engines)
On some early production 1957 272, 292, 312 engines, oil leakage may occur between the crankcase ventilation cover and the cover gasket. This leakage can result from the use of the vent screen assy (EAD-6841-A) which is too long and does not allow the cover to seat properly on the gasket.
To eliminate this oil leakage , use metal cutting shears to trim the vent screenassy to a length of 1 13/16 inches.
I found this in my service bulletins and thought I'd share,
Kevin Bigwin
Kevin S in Akron, Ohio