1977/07/11 Caterpillar

New Adjustment Pin And Valve Seal Used In Fuel Ratio Control{1278}

Usage:

825B, 826B Compactors;
D343, D346, D348, D349, D353, 1693, 3406, 3408, 3412 Engines;
245 Excavators;
983, 988B, 992B Loaders;
16G Motor Graders;
594H Pipelayers;
657B Scrapers;
D9H, 621B, 623B, 631D, 633D, 637D, 641B, 650B, 651B, 657B, 660B, 666B, 768B, 772, 776, 824B Tractors;
769B, 773, 777 Trucks

Description of Change: A new adjustment pin and valve seal are now used in fuel ratio control for the above listed models. The new pin is made of a plastic material. The former pin was made of steel and some times gouged (made a hole) and stuck (will not move) in the cap. This caused a change in the engine performance. The new pin will prevent these problems.

The new valve seal is made of a material that has more resistance to becoming hard with age. Some of the former seals became hard and cracked or broke.

Adaptable To: Direct replacement.

Caterpillar Information System:

1977/07/11 Baffle Added To Water Pump Cover To Send Coolant In Bypass Line Directly Into The Water Pump{1361}

1977/07/11 Some Earlier Vickers Hydraulic Pump Groups Are Not Available For Parts Service--Some Modification Is Needed To Install Replacement Pump Groups{5055}

1977/07/11 Tools To Install Crankshaft Seal And Wear Sleeve{1160,1161,0622}

1977/07/04 New Procedure For Calibration Of 1P3060 Pyrometer Group{0653,1050}

1977/07/04 New Seal For Crankshaft{1161}

1977/07/04 Use New Procedure To Tighten Flywheel Housing Bolts{1157,1201}

1977/07/04 Tools To Hone (Machine) Cylinder Liners Are Available To Permit The Use Of Used Cylinder Liners With New Style Pistons{0664,1214,1216}

1977/06/27 Service Tools For Low Emission Truck Engines With EGR{0650,1059,1080}

1977/06/27 New Aftercooler Housings And Covers Have Improved Design{1063}

1977/06/27 Correct Rebuild Kits Must Be Used For Repair Of Earlier And Later Water Pumps{1361}

1977/06/27 More Of The Oversize (Larger) Cast Iron Seal Rings Are Available For Clutch Housings And Clutch Pistons{3169,3170}

1977/06/20 Socket For Removal And Installation Of Fuel Injection Pump Bushings is Now Stronger{0612,1253}

1977/07/11 Safety Vent Caps For Caterpillar Batteries{1401}

1977/07/11 New Component Code List For Use In The Service Information Retrieval System{0331,0374}

1977/07/11 Heat Absorbing Material Aids And Protects Surface Areas Being Welded Or Heated{0680}

1977/07/11 New Inserts To Repair Cylinder Liner Seats On D353 Engine Blocks{1201,1216,1217,0663,0653}

1977/08/08 Correct Adjustment Of Fuel Shut-Off Solenoid Shaft Can Prevent Failures{1259}

1977/08/08 New Vickers Pump Design{5055}

1977/08/08 Larger Boss Used In Cylinder Block So Bolt Hole Will Not Be Drilled Into Coolant Passage{1201,1350}

1977/08/08 Spacers Added To Alternator Group To Improve The Mounting{1405}

1977/08/08 New Air Inlet Manifold Has Longer Bolt Bosses With More Thread Depth To Keep Bolts Tight{1058}

1977/08/08 Clean Bolt Holes In Cylinder Block Before Cylinder Heads Are Installed{1101,1201}

1977/08/15 Tools From Caterpillar To Test And Charge Air Conditioners And For Repair Of Frigidaire Compressors{7320,0651}

1977/08/22 New Main And Connecting Rod Bearings Are Made Of Higher Strength Material{1230}