1955 Corvette: Service Bulletin: V8 Engines
Model Year: 1955 V8 Engines
Subject: 1955 V8 Engines
Source: Chevrolet Service Bulletin
Bulletin Number: 55 - 4
Date: November 23, 1954
TO: ALL CHEVROLET DEALERS
OIL CONSUMPTION AND SMOKING
We have received several complaints regarding excessive oil consumption and smoking on early 1955 Chevrolet V8's. When such a condition exists, please be guided by the following procedure:
Install Part Number 3836755, Valve Stem Oil Shields (Shedders). These are inverted cups to be installed over each intake and exhaust valve spring to control the amount of oil going to the valves. (The internal valve stem oil shields which are on all early model intake valves should be removed and the above part number installed).
This new Valve Stem Oil Shield, Part Number 3836755, should be available for use approximately December 15, 1954 from Zone Warehouses.
After installation of valve stem shields, these engines should be run at least 1,000-2,000 miles to permit the proper seating of rings before any further work is performed as it pertains to piston ring replacement. In the event piston rings must be replaced, the "98" oil ring, Part Number 3719631, should be used and is available through Zone Warehouses. No other ring should be used as no other ring known will compare with the good performance of the "98" oil ring. When the rings are replaced, the bores should be rough honed in the usual manner.
PISTON RING NOISE
In a few instances, we have run into piston ring noise. Piston ring noise telephones up through the oil filler cap. It may also be dampened out by holding the hand over the oil filler tube when cap is removed.
In cases where piston ring noise caused by oil ring rail vibration which may be audible at idle and at fast idle, rings should not be replaced under 1,000 miles if oil consumption is not involved as the noise will disappear in some rings from 500 to 1,000 miles.
FUEL PUMP NOISE
There have been some cases where the fuel pump push rod has been noisy - this may be checked out by removing the fuel pump and running the engine.
This noise may be eliminated by installing a Weatherhead flexible line #11079, between the gas line from the gas tank and the fuel pump. This has been released for production.
EXHAUST MANIFOLD GASKETS
Manifold exhaust gaskets are no longer being used in production on V8 engines. The gasket was eliminated to prevent loosening of the manifold bolts. .040" stock will be added to the manifold to compensate the gasket. The manifold bolts should be torqued from 25 to 35 foot pounds to prevent leakage. Heavy graphite grease should be used between manifold and head, and as a sealant when bolts are removed and replaced.
The above information is given to you only for the use and guidance of your Service Deparment personnel.
Zone Service & Mechanical Manager