New Piston Group With Better Service And Operation Characteristics Now Available
Usage:
D379, D398, D399 Industrial and Marine Engines
Description of Change: A new piston with several improvements is now used in D379, D398 and D399 Industrial and Marine Engines.
The improvements are:
-
- ... better heat distribution in the crown section.
- ... removal of heat plug boss.
- ... ring band insert with flat sides used in place of keystone type insert.
- ... top land is machined smaller to a level below the valve pocket. This gives more clearance between the piston and liner to prevent wear to the piston in the area of the top land.
- ... better heat distribution in the crown section.
Adaptable As: Direct replacement as shown in the charts that follow and adaptable to all earlier models:
Show/hide table
| NOTICE |
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The new piston must not be assembled in a used cylinder liner that has a wear ridge (condition where two surface levels can be felt) near its top.
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A procedure to remove the wear ridge in used cylinder liners is given in Special Instruction Form SEHS7220.
Caterpillar Information System:
1978/05/03 New Oil Pressure Gauge Available For Marine Transmissions Used On D348, D349, D353, D379, D398, D399, 3406 And 3408 Marine Engines
1978/05/03 External (Outside) Oil Lines Now Used Instead Of The Oil Passage In The Cylinder Block And Flywheel Housing
1978/05/03 Possible Problems With Fuel Filters
1978/05/03 One-Piece Seat Used For Governor Spring
1978/05/03 New 5P8709 Piston Tool Group For The Alignment Of Piston Cooling Jets
1978/05/03 Improved Oil Suction Tube Assembly
1978/05/03 O-Ring Seals Of A Different Material Are Now Used On The Outside Diameter Of The Servo Cylinder In Governors
1978/05/03 Longer Hoses Used At Radiator Lower Hose Connections
1978/05/03 New 5P7335 Rack Adjusting Tool Available
1978/05/03 List Of Service Publications
1978/05/03 Oil Grooves And Harder Gears Are Now Used In The Oil Pump On 6.25" Bore Vee Engines
1978/05/03 Procedure For Alignment Of Transmission Mounting Parts On 1100 Series And 3208 Truck Engines With Allison MT640, MT650, And AT540 Series Transmissions
1978/05/03 Chamfer Added To Bolt Hole In Auxiliary Drive Pulley For Water Pump
1978/05/24 Stronger Fuel Inlet Flanges Prevent Parts Damage And Keeps Air Out Of The Fuel System
1978/05/24 Use New Tools To Adapt Former Cylinder Heads With Counterbores To Cylinder Blocks With Spacer Plates
1978/05/24 New Drive Belt Idler Pulleys Have Larger Bearings
1978/05/24 Coolant Syringe And Battery Fluid Probe Now Available
1978/05/24 New Gasket Installed Between Flywheel Housing And Cylinder Block
1978/05/24 Silicone Grease Now Used In Seal Ring Groove In Turbochargers
1978/05/24 New Governor Spring Gives Correct Balance Point Speed
1978/05/24 If Auxiliary Bypass Oil Filters Are Used-Be Sure To Add Enough Extra Oil To Fill The Filters
1978/05/24 Modification Of Drive Adapter For Fuel Injection Test Bench
1978/06/14 Lubrication For A Rebuilt Engine
1978/06/14 5P9722 Driver Needed To Install New Seal Assembly In Water Pumps