Fuel Injector Trim Bolt {1257}
Usage:
All 3500 And 3600 Families of Engines
A trim bolt is provided on the injectors for the above engines to adjust the rack zero point at the factory. This allen head bolt should NOT be moved, adjusted or tightened in the field. There have been instances where customers have mistaken this allen head bolt for a fastener rather than an adjustment. See illustration.
NOTE: If this trim bolt is moved, the fuel injector must be removed from the engine and completely recalibrated. Low power and an imbalance of fuel going into each cylinder can result. This causes unequal power output from each cylinder.
Location of 5P9653 Bolt in fuel injector rack.
Caterpillar Information System:
1987/06/01 Remanufactured Programmable Electronic Engine Controls (PEEC) {1250}
1987/06/01 Use Correct Pistons And Rings For 3406B Truck Engines {1214,1215}
1987/06/01 Use Only Paint To Mark Connecting Rod Caps For Torque-Turn Method {1218,1219}
1987/05/25 Truck Performance Diagnostic Guide Available{0374,1219,1227}
1987/05/25 Remanufactured Heavy-Duty Starters And High-Amp Alternators{1405,1453}
1987/05/25 Improved Start Switch Used{1416}
1987/05/25 New Service Tools Available{0600}
1987/05/25 1U5796 Pressure Differential Gauge Group Available For Load Sensing Hydraulic Systems and Differential Steering System{0770,0784,5050}
1987/05/18 Improved Oil Temperature Regulator Gasket{1330}
1987/05/18 New Precombustion Chamber Seal Available{1100,1106}
1987/05/18 Be Sure Tubing Clamps That Fasten Air-To-Air Aftercooler To Air Lines Are Correctly Installed{1058}
1987/05/18 Hollow Dowel Relieves Accessory Drive Oil Leakage{1207,1166}
1987/06/01 Features And Servicing Of The Various Caterpillar 3161 Governors {1264,1278}
1987/06/01 Exhaust Manifold Thermocouple Has Longer Insulated Leads {1050,1408}
1987/06/15 Caterpillar Original Equipment Paint Products (U.S. And Canada) {7559}
1987/06/15 New Face Films For Electronic Monitoring System (EMS) Panels {7490}
1987/06/15 1U5495 Latch Group Available For Earlier Large Duo-Cone Seal Installers {0700,4052}
1987/06/15 New 1U5752 Retainer Tool Available To Service Hydrostatic Transmissions {0721}
1987/06/15 New 1U5230 Hand Pump (General Purpose Hydraulic) Available {0646}
1987/06/15 New Relief Valve Guide Used In Oil Pump Groups {1304}
1987/06/15 All Three Main Bearing Part Numbers Stamped On Lower Portion Of Standard Size Bearing {1203}
1987/06/15 Use Of Crankshaft Seal Adapter Eliminated {1150,1160,1161}
1987/06/29 Recommendations For Reusability Of Pistons With Crater Rim Cracks{1214}
1987/06/29 New Water Pump Group Used{1361}