1982/03/29 Caterpillar

Location Of Sending Unit Changed To Improve Accuracy Of Water Temperature Indication{7453}

Usage:

3408, 3412 Industrial And Generator Set Engines

The location of the sending unit for the water temperature gauge has been changed for the above engines. The 5L7442 Sending Unit, which is part of the 3N8246 Sender Group, has been moved from the rear of the left cylinder head to the front of the right cylinder head on engines so equipped.

This change moves the sending unit away from the turbocharger exhaust manifold and the exhaust crossover lines. The move improves the accuracy of the temperature indication.

At its former location, heat from the manifold caused the sending unit to give an indication that was higher than the engine temperature. Heat from the crossover lines some times burned the line which connects the sending unit to the gauge.

The 5L7442 Sending Unit can be moved to the new location as shown in the illustration on all earlier 3408 and 3412 Industrial and Generator Set Engines.

New location of sending unit.

Caterpillar Information System:

1982/03/29 Parts Book Changes{0374}

1982/03/22 Improved Plunger And New Spring Used In Mechanical Shutoff Group{7418}

1982/03/22 Use FT1614 Cover To Protect Center Shaft Assembly{0622,3305,3306,3302,3307}

1982/03/22 Correct Use Of 6V2023 Flow Check Adapter Group Is Important To Prevent Damage To An Engine{0651,0654,1250}

1982/03/22 Caterpillar Electric Starting Motors{1453,1407}

1982/03/22 Use 5P5195 Fuel Line Wrench Correctly{0612,1252}

1982/03/22 Improved Valve Cover Seal Used{1107}

1982/03/22 Engine Replacement{1000}

1982/03/22 Use Correct Torque On Hydraulic Valve Bolts, Nuts And Taperlock Studs{5050}

1982/03/22 Carbon Build-Up In Combustion And Inlet Areas{1058,1101,1105,1214,1104}

1982/03/15 New Oil Pump Outlet Elbow Is Stronger{3314,3310}

1982/03/15 Use The 6V6059 Microlite With The 6V2196 Inspection Microscope{0651}

1982/03/29 Flywheel Adapters For Dynamometer Testing{1156,0652}

1982/03/29 Multi-Piece Wheel Rims; Caution Must Be Used{4202,4201}

1982/03/29 New Regulator Group Increases Coolant Flow To Cab Heater, Prevents Overcooling{1355}

1982/03/29 Twisted Port Plate Can Cause Excessive Case Drain From Piston Pump Or Motor{5058,5070}

1982/04/05 Lubricant Recommendations Have Been Changed For Vehicular Products{0680,0374,0375,3004,1318,5060}

1982/04/05 Conversion Of 49-State 3406 Truck Engine From 283 kW (380 hp) To 298 kW (400 hp) Arrangements{1000}

1982/04/05 Reminder: Check Valve Lash Adjustment At Correct Intervals{1102}

1982/04/12 Pressure Regulator Group Now Available For Parts Service{3152,3185,3166,3012}

1982/04/12 Use Correct Part Numbers For Main And Connecting Rod Bearings{1230,1203,1219}

1982/04/12 Lock Screw For Threaded Crown On Hydraulic Cylinders No Longer Used{5000}

1982/04/12 Make Sure Hydraulic Pumps Are Installed Correctly{5055,5070,5073}

1982/04/12 New Seals Improve Pressure Regulator Group{3185,3012}