SENSOR GP-POSITION 2691981 - Caterpillar

Introduction
For Specifications with illustrations, make reference to Specifications for 3208 Industrial & Marine Engines, SENR4606. If the Specifications in SENR4606 are not the same as in the Systems Operation and the Testing & Adjusting, look at the printing date on the front cover of each book. Use the Specifications given in the book with the latest date.Fuel System
Engines With Serial Numbers 90N1-90N6120
Schematic Of Fuel System
(1) Return line for fuel injection nozzles. (2) Fuel priming pump. (3) Return line for constant purge valve. (4) Constant purge valve. (5) Manual purge valve. (6) Fuel injection nozzle. (7) Fuel tank. (8) Fuel inlet line. (9) Fuel filter. (10) Bypass valve (for fuel priming pump). (11) Fuel transfer pump. (12) Fuel bypass valve. (13) Camshaft. (14) Fuel injection pump housing. (A) Check valve. (B) Check valve. (C) Check valve. (D) Check valve.The sleeve metering fuel system is a pressure type fuel system. The name for the fuel system is from the method used to control the amount of fuel sent to the cylinders. This fuel system has an fuel injection pump for each cylinder of the engine. It also has a fuel transfer pump on the front of the fuel injection pump housing. The governor is on the rear of the fuel injection pump housing.The drive gear for the fuel transfer pump is on the front of the camshaft for the fuel injection pumps. The carrier for the governor weights is bolted to the rear of the camshaft for the fuel injection pumps. The fuel injection pump housing has a bearing at each end to support the camshaft. The camshaft for the sleeve metering fuel system is driven by the timing gears at the front of the engine.The fuel injection pumps, lifters and rollers, and the camshaft are all inside of the fuel injection pump housing. The fuel injection pump housing and the governor housing are full of fuel at transfer pump pressure (fuel system pressure).
Diesel fuel is the only lubrication for the moving parts in the transfer pump, fuel injection pump housing and the governor. The fuel injection pump housing must be full of fuel before turning the camshaft.
This fuel system has governor weights, a thrust collar and two governor springs. One governor spring is for high idle and the other governor spring is for low idle. Rotation of the shaft for governor control, compression of the governor springs, movement of connecting linkage in the governor and fuel injection pump housing controls the amount of fuel sent to the engine cylinders.
Cross Section Of Fuel System
(11) Fuel transfer pump. (13) Camshaft. (14) Fuel injection pump housing. (15) Lever. (16) Governor housing. (17) Load stop pin. (18) Cover. (19) Sleeve control shafts (two). (20) Inside fuel passage. (21) Drive gear for fuel transfer pump. (22) Lever on governor shaft. (23) Governor springs (inner spring is for low idle: outer spring is for high idle). (24) Spring seat. (25) Thrust collar. (26) Overfuel spring. (27) Load stop lever. (28) Carrier and governor weights. (29)