1979/08/22 Caterpillar

New Cylinder Head Gasket Has Smaller Diameter Cylinder Openings To Improve Location Of Combustion Seal Ring

Usage:

D353 Engines (46B, 47B, 77B)

Description of Change: A new cylinder head gasket is used on the above models. The new gasket has cylinder openings which are .106" (2.69 mm) smaller in diameter than the openings in the former gasket. This changes the location of the combustion seal ring in relation to the cylinder liner flange, so the ring will have positive support. Formerly, the seal ring was in a location near the edge of the liner flange and, with normal tolerances, it was possible for the ring to be in a position beyond the edge of the liner flange. In this position, the ring does not have good support and will become damaged during operation.

Adaptable As: The new 8N7264 Gasket is a direct replacement for the former 7N3083 Gasket, which is canceled. Two are used per engine.

Caterpillar Information System:

1979/08/22 New Design Thrust Plate Used In Crankshaft Group

1979/08/22 Only One Dowel Pin Is Now Used To Hold The Thrust Bearing In The Correct Position

1979/08/22 Exhaust Manifold And Air Lines Groups Changed To Prevent Exhaust Leakage

1979/08/22 New Seal Used Under Retaining Bushing For Fuel Injection Pump Bonnet

1979/08/22 When Timing The Engine, Be Sure The Timing Bolt Is Installed In The Correct Hole In The Flywheel

1979/08/22 Turbocharger Bearings Are Now Available In More Different Sizes For Better Turbocharger Reconditioning

1979/08/22 New Rear Cover And Gasket Used On Water Pump

1979/08/22 New Governor Housing Assembly Used In Governor And Fuel Injection Pump Group

1979/08/22 Why Engines Are Damaged By Fuel Sulfur

1979/08/08 New Water Pump Assemblies Use An Improved Seal Assembly

1979/08/08 Changes Made To 8S2243 And 8S4613 Wrenches Used On Fuel Injection Pumps

1979/08/08 Installation Of Stronger Transmission Mounting Parts

1979/08/22 Sealant Now Used On Pipe Plugs At The Bottom Of The Oil Filter Base Assembly To Prevent Oil Leakage

1979/08/22 List Of Service Publications

1979/08/22 New Rocker Arms And Rocker Arm Shaft Have Improved Lubrication

1979/09/19 Engines Can Use Crankshafts With Either Six Or Eight Counterweights

1979/09/19 6V190 Clamp Is Available For Use On Sleeve Metering Fuel Systems

1979/09/19 Different Grease Fitting Now Used In Fan Drive Group

1979/09/19 Keystone Piston Groups Can Be Installed In Earlier Engines In Steiger Tractors

1979/09/19 Tee Handle Hexagonal Wrench In Rack Adjusting Tool Is Now Available For Parts Replacement

1979/09/19 New Main And Connecting Rod Bearings Have A Thicker Layer Of Surface Material

1979/09/19 Pin Bore Is Now Offset (Not In The Center) .059" (1.5 mm) In The Piston To Stop Vibration Of The Cylinder Liners Which Can Cause Pitting On The Coolant Side Of The Cylinder Liners

1979/09/19 Service Kit Is Available For Woodward UG8 Governor

1979/09/19 New Bracket Available For Installation Of Jacket Water Heater