00-06-01-012D Use of Surface Conditioning Disks When Cleaning Engine Gasket Sealing Surfaces and or Reused Engine Parts - (Oct 25 2011)
|Subject:||Use of "Surface Conditioning Disks" When Cleaning Engine Gasket Sealing Surfaces and/orReused Engine Parts|
|Models:||2013 and Prior GM Passenger Cars and Trucks|
This bulletin is being revised to add the 2010-2013 model years and add AlternativeCleaning Method. Please discard Corporate Bulletin Number?00-06-01-012C (Section 06– Engine/Propulsion System).The Use of "Surface Conditioning Disks"
Notice:Do not use abrasive pad/bristle devices to clean the gasket surfaces of engine components.Abrasive pads should not be used for the following reasons:Abrasive pads will produce fine grit that the oil filter will not be able to removefrom the oil. THIS GRIT IS ABRASIVE AND HAS BEEN KNOWN TO CAUSE INTERNAL ENGINE DAMAGE.Abrasive pads can easily remove enough material to round cylinder head surfaces. Thishas been known to affect the gasket's ability to seal, especially in the narrow sealareas between the combustion chambers and coolant jackets.Abrasive pads, wire and abrasive rubber finger wheels can also remove enough metalto affect cylinder head, block, oil pan rail, and intake manifold runner flatness,which can cause coolant and oil leaks and air leaks. It takes about 15?seconds toremove 0.203?mm (0.008?in) of metal with an abrasive pad.Abrasive pads, Abrasive rubber fingers wheels & wire wheels with high speeds grindersproduce air bourne debris that can travel throughout the shop contaminating otherwork being performed outside of the immediate work area.
When cleaning engine gasket sealing surfaces and/or cleaning parts from an enginethat are to be reused, surface conditioning disks (typically constructed of wovenfiber or molded bristles) that contain abrasives, such as a high amount of AluminumOxide, should NOT be used.
The use of such surface conditioning disks dislodges Aluminum Oxide (from the disk)and metal particles, which can lead to premature engine bearing failure.
The presence of Aluminum Oxide in engine oil has been shown to cause premature enginebearing failure. In some cases, this failure occurs in as little as 2,200?km (1,000?mi)or less after the repair has been made.
Surface conditioning disks may grind the component material and imbed it into thedisk. This can result when more aggressive grinding of the gasket surface takes place.Recommended Cleaning Procedure
General Motors recommends the use of a razor blade or plastic gasket scraper to cleanthe gasket surface on engine components that are to be reused. When cleaning gasketsurfaces, please note the following:When using a razor blade type gasket scraper, use a new razor blade for each cylinderhead and corresponding block surface. Hold the blade as parallel to the gasket surfaceas possible. This will ensure that the razor blade does not gouge or scratch the gasketsurfaces.Do not gouge or scrape the combustion chamber surfaces.Do not gouge or scratch any engine-sealing surface during the cleaning process.
Alternative Cleaning Method:
To properly clean the sealing surface prior to reassembly, GM Low VOC Cleaner, P/N?19287401(in Canada, PN-88901247), should be sprayed on the mating surface.