1996/12/23 Caterpillar

New Thinner Exhaust Manifold Gasket Used{1059}

Usage:

3406C (8PN11264-Up),
3406E (5EK97094-Up) Truck Engines

Description of Change: A new 0.35 mm (.014 in) thinner exhaust manifold gasket is now used on these engines. The new thinner exhaust manifold gasket will retain the exhaust port sleeves better.

(X) = Earlier exhaust port with sharp edge (A). (Y) = Current exhaust port with radiused edge (B). Exhaust port sleeve (C).

Adaptable To: The new 138-4611 Exhaust Manifold Gasket is a direct replacement for the former 129-9453 Exhaust Manifold Gasket. The former gasket is canceled. The new exhaust manifold gasket is in effect as shown in the subtitle.

Effective with the same truck engines, the edge of the cylinder head exhaust ports has been given an approximate 1.5 mm (.060 in) radius (B). See the illustration. This radius helps prevent the exhaust port sleeve (C) from seating on the sharp edge (A) of the exhaust port.

Before a new 138-4611 Exhaust Manifold Gasket is installed on an earlier engine for the first time, Caterpillar recommends using a hand grinder to put an approximate 1.5 mm (.060 in) radius on the edge of the exhaust ports.

NOTE: Caterpillar recommends the exhaust port sleeves be replaced during a major overhaul. The 3406C (8PN) Truck Engine uses the 102-7578 Exhaust Port Sleeve. The 3406E (5EK) Truck Engine uses the 101-6706 Exhaust Port Sleeve.

Caterpillar Information System:

1996/12/23 July 1996 Software Release{1902}

1996/12/23 Check Turbocharger Seals If There Is A Sudden Increase In Crankcase Blowby{1052,1317}

1996/11/01 Fuel Injection Pump Bushings Have New Groove Adjacent To Load Ring {1251}

1996/11/01 Improved Fuel Pump Plunger Helps Prevent Plunger And Sleeve Scuffing In Service 8.5 mm Fuel Injection Pump Assembly For Sleeve Metering Fuel System (SMFS) Governor And Fuel Injection Pump Groups{1251,1286}

1996/10/01 Improved Water Pump Groups Available{1361}

1996/10/01 New O-Ring Seals Used On "Through-Head-Adapter" And "Internal Fuel Lines" In Fuel Injection Lines Groups{1252}

1996/10/01 Procedure For Installing Steel Core Gasket At The Front Housing And The Flywheel Housing{1151,1157,1162}

1996/10/01 New Torque Specification For Injector Rocker Arm Adjustment Lock Nut{1123}

1996/10/01 An Improved O-Ring Seal And Proper Use Of Adapter Locks Reduces Oil Leaks{1252}

1996/09/01 New Control Group Does Not Have An Oil Pressure Sensor And Requires Installation Of A Sensor Kit {1904,1924}

1996/09/01 New Governor Weight And Race Increase Durability {1264}

1996/09/01 Use Two Piece Ferrous Articulated Pistons Instead Of Aluminum Pistons {1214,1331}

1996/12/23 New Oil Supply And Drain Lines In Turbocharger Oil Lines Groups Used With "Mid-Mount", "New Mid-Mount", And "Low Mount" Arrangements{1307}

1997/01/27 New Remanufactured Water Pump Groups Include Cast Iron Impellers{1361}

1997/01/27 Description Of August 1996 (AUG96) Software Modifications{1902}

1997/01/27 Points To Remember When Replacing A Viscous Crankshaft Damper Assembly With A Rubber Crankshaft Damper Assembly{1205}

1997/01/27 Timing Procedure Aid -Alignment Of Timing Gear Marks On 3406 Engines{1206}

1997/01/27 New Gasket Used Between Air Compressor And Front Housing{1803}

1997/02/24 New O-Ring Seal Used In Hydraulically Actuated Electronic Unit Injector (HEUI) Pump Group{1714}

1997/02/24 New Specifications For Pressure Drop Across The Air-To-Air Aftercooler{1063}

1997/02/24 Improved Bushing O-Ring Seal Available For Injection Pump Groups{1251}

1997/02/24 Summary Of Changes To Timing Advance Drive Groups (Update){1272}

1997/02/24 New Oil Supply And Drain Lines In Turbocharger Oil Lines Groups Used With "Mid-Mount", "New Mid-Mount", And "Low Mount" Arrangements{1307}

1997/04/01 Improvements Made To Remanufactured 0R-3008 Fuel Transfer Pump{1256}