ROLLER GP-TRACK-DOUBLE FLANGE 3843275 - Caterpillar

New (A) and former (B) piston groups.Adaptable To: The different components in the new and former piston and rod groups are listed in Chart A. The components of the new and former piston groups are identified in the illustration and listed in Chart B. The new two piece pistons are in effect in the machines as listed in Chart C. When used together in a complete set, the new components in Chart B, are a direct replacement for the former components. Both new and former pistons can NOT be used together in the same engine. The new pistons are heavier than the former pistons.
A new cylinder liner MUST be installed when replacing a former piston with a new two piece piston. The top ring will be closer to the top of the new piston than the top ring on the former piston. A used cylinder liner will have a slight wear step at the end of the ring travel. This wear step could cause the top ring to break if the new piston is installed in a used liner. When a new two piece piston is used to replace a former piston, the former 9Y4121 Cooling Jet Assembly and 1W4188 Jet Retainer MUST be replaced by the new 7E4069 Cooling Jet Assembly and 7C3722 Jet Retainer. The new two piece piston must be used with the 7C8608 Connecting Rod Assembly. The new piston can NOT be use with the former 1W4800 or 8N6020 Connecting Rod Assembly because the top of the rod would interfere with the underside of the piston crown. The 7C8608 Connecting Rod Assembly can be identified by the part number 7C8007 forged on the rod. The new 6I1657 Governor replaces the former 7E7249 Governor on engines with the new two piece piston. The former governor can be adjusted to the same specifications as the new governor.
To adjust the governor on the engine, see Reference Special Instruction, SEHS9240-01. The new on-engine static setting numbers are: 1st Break Point 3.78 mm2nd Break Point 9.28 mmFULL TORQUE SETTING 10.80 mm (set with power setting screw)
To adjust the governor on the test bench, see Reference Special Instructions, SEHS9318-01 and SEHS9351. The new fuel test bench setting numbers are: Col 13 2587 rpm 8.00 TSDCol 2 2541 rpm 21.00 TSDCol 14 2500 rpm 23.28 TSDCol 15 2400 rpm 26.17 TSDCol 16 2300 rpm 28.23 TSDCol 17 1950 rpm 29.63 TSD1st Break Point 2537 rpm 22.20 TSD2nd Break Point 2333 rpm 28.10 TSD
The Fuel Air Ration Control, Pneumatic Speed Control, Low Idle Offset, High and Low Idle settings have not changed.
With the use of the new two piece pistons, Caterpillar recommends the use of multi-viscosity Cat Engine Oil (EO). If an oil other than EO is to be used, it must meet API specifications CF-4, CF-4/SG, CF-4/SF, CE, CE/SG, CE/SF.