Disassembly and maintenance of the Big Boy

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Shell removal


Valve Hanger and Piston guide interference.


Front driver removal


Removal of the bottom plate


Exposed journals and drive gearing.


Drivers can be removed as an assembly


Motor Removal


Drive coupling details


Valve hanger and piston rods can be removed as an assembly

To access drive gears remove these scrwes.
Do not loose the insulators and insulator pin at rear hole .

The worm gear can now be pressed out if needed

Tie wraps added to help control the wiring at rear truck.


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