1978/02/06 Caterpillar

Probable Causes Of Low Fuel Delivery During Testing On Fuel Injection Test Benches{0650,1250}

Usage:

There can be several causes for constant low fuel delivery from the separate injection pumps of pump housing groups during testing on Fuel Injection Test Benches. The first is worn or damaged plunger and barrel assemblies. Test bench operators can install new plunger and barrel assemblies and check the fuel delivery again.

If fuel delivery is still low, check the master valve (special fuel injection valve with a flat seat used as the standard resistance against which the fuel injection pump must work). To do this, exchange the master valve with a master valve that shows normal fuel delivery.

If the master valve checks correctly, look for a restriction at the ends of the fuel injection lines. Generally, restrictions are caused when the line fittings are tightened too tight or if they have been used for long periods of time. A.062" (1.57 mm) drill can be used to clean the lines of these restrictions.

Troubleshooting problems like these will be added to Special Instruction Form GEG00451-01, "Using the Caterpillar Fuel Injection Test Bench", when revisions are made.

Caterpillar Information System:

1978/02/06 New Water Temperature Regulator Opens At 180°F (82°C){1350,1355,7304}

1978/02/06 Attachment Groups Put Corrosion Inhibitor Directly Into Cooling System{1350}

1978/02/06 Successful Engine Service-3208 Engine Booklet Is Available{1000}

1978/02/06 Smaller Quantity Of Oil Now Used In Engine Oil Pan; Prevents Contact Between Crankshaft And Oil{1318}

1978/01/30 Do Not Change Factory Fuel Or Speed Settings On Truck Engines Unless New Settings Are Certified Under Applicable EPA Regulations{0336,0337,1257}

1978/01/30 Stronger Front Support Assembly{1153}

1978/01/30 New Water Pump Cover Has A Baffle And Wall To Send Coolant Flow From Bypass Line Directly Into Water Pump{1361}

1978/01/30 Oil Strainer (Screen) Added To Turbocharger Thrust Bearing{1052,1053}

1978/01/30 Valve Damage Can Be Caused By Short Intervals Of Engine Operation In Very Cold Temperatures{1105,1208}

1978/01/23 Change In Design Of Engine Governor, Fuel Injection And Transfer Pump Groups, And Fuel Ratio Control Groups{1264,1278,1286}

1978/01/23 Design Of Governor Control Linkage Changed; Less Force Is Needed To Move The Accelerator Pedal{1265,1269}

1978/01/16 Improved Gasket Prevents Oil Leakage From The Governor{1264}

1978/02/13 Replacement Seal Group For Water Pump Impeller Now Has All The Seal Parts Plus An Installation Tool{1361,0622}

1978/02/13 Complete Set Of Contact Points For Dial Indicators Is Now Available In One Group{0653}

1978/02/27 New Seal Assembly With Longer Ferrule Prevents Damage To Ferrule During Cylinder Head Installation{1100,1101,1300}

1978/02/27 Fabricated Adapters Permit Horizontal Mounting Of Transmissions On 1P2420 Transmission Repair Stand{0640}

1978/02/27 Replacement Seals And Wear Sleeves Now Available As A Crankshaft Seal Kit{1202,1160,1161}

1978/02/27 Stronger Exhaust Manifold Gasket Now Used{1059}

1978/02/27 Improved Fuel Priming Pump Assembly Has Better Sealing Characteristics; Repair Kit Available For Knob{1258}

1978/02/27 Modification Of Oil Pan For Installation Of Oil Sump Heater{1302}

1978/02/27 New Tachometer Drive Adapter Assembly Prevents Failure Of The Seals For the Tachometer Drive Group And Transfer Pump{7462,1256}

1978/03/06 Stronger Piston And Connecting Rod Are Tapered In Area Of Piston Pin{1213,1214,1218}

1978/03/06 5P8558 Pressure Gauge Calibrating Group Checks Pressure Gauges{0650}

1978/03/06 Use Again Specifications For Valve Springs Are Changed{1108}