1988/04/04 Caterpillar

Stepped Compression Ring Temporarily Used{1214,1215}

Usage:

3208 ( 51Z ) Truck Engines

Description of Change: For a period of time, a stepped compression ring was used on pistons in 3208 Naturally Aspirated Truck Engines. This ring is used in engines with serial numbers 51Z70653-51Z72766. Effective with 51Z72777, the former ring is reinstated. This change was made to evaluate the effects of the step-type ring on emissions and oil control.

Adaptable To: The stepped 2W2178 Ring can be installed if desired in all earlier 3208 NA Truck Engines as a direct replacement for the former 9L6233 Ring or earlier compression rings. Install the ring so the step is on the bottom face of the ring. (See Special Instruction SMHS8409-01 packaged with the ring.) The word "UP" appears on the other side of the ring. The 2W2178 Ring has been available for parts service and used in rebuilt engines for several years.

Caterpillar Information System:

1988/04/04 Use Improved Heat Start Switch{1416}

1988/04/04 Method To Reduce Indicator Contact Point Breakage{0760}

1988/04/04 Sealed Beam Halogen Lamps Are Available{7309}

1988/03/28 Polarity Corrections On Wiring Diagrams{4450}

1988/03/28 New 1U6602 Tachometer Group Available{0775,0781}

1988/03/21 New Power Pad Housings With Needle Bearings Used In Fuel Injection Control Groups{1264}

1988/03/21 New Publication Available-"Diesel Fuels And Your Engine"{0374,0375,0645}

1988/03/21 Service Tools For Reintjes Marine Gears{0723}

1988/03/14 New Connecting Rod Assembly Used{1218}

1988/03/14 New Auxiliary Water Pump Group Used{1371}

1988/03/14 Use The Correct Oil In Spark-Ignited Engines{1300}

1988/03/14 Magnetic Switches (Starter Relays) Improved{1450}

1988/04/04 Fuel Ratio Control Diaphragms And Settings On 3161 Governors{1278}

1988/04/18 Extraction Tools For "Live Oil Sampling"{7770,0770,0781,0783,0784}

1988/04/18 Some Components Of The Variable Pulley And Adjustable Pulley On The Kent-Moore Fuel Injection Test Bench Are Available From Caterpillar{0782}

1988/04/18 1" 8T9141 Offset Sledging Wrench Available{0602}

1988/04/18 How To Identify Failures To Electric Jacket Water Heaters{1383}

1988/04/18 Former Exhaust Valve Bridge For Jacobs Brake® Interferes With 40 mm Nozzle Adapter; New Bridge Used{1119,1100}

1988/04/18 Modification To Prevent Oil Leaks Around Governor Control Shaft{1265,1287}

1988/04/25 New 1U8115 Generator Test Lead Set With Insulated Tips {0785}

1988/04/25 New Diaphragm For Brakesaver Control Valve {1159,1155}

1988/04/25 New Socket In Valve Rocker Arms Provides Lubrication For Inlet Valve Seats {1103,1105,1123}

1988/04/25 Improved RH Watercooled Exhaust Manifold And Exhaust System Sealing {1059,1070,1061,1050}

1988/05/02 Diode Added To Prevent Damage To Time Delay Relay {7421}