Abstract: A fuel stoker for removable attachment to the access port of a solid fuel furnace has a bin for receiving fuel such as coal and a chamber carrying a piston, located at the bottom of the bin, for periodically throwing a charge of coal on top of a fire. A spring-loaded bar, pivotable by one end on the bin, is connected to the piston via a linkage, and spring-biased to advance the piston towards the fire. A spiral cam having a sudden drop-off is intermittently rotated one revolution by a motor to retract the piston and allow fuel to drop into the chamber. At the drop-off, the piston is suddenly advanced to throw the fuel onto the fire. The drive shaft also operates an agitating poker and a grate shaker during the fuel loading phase of operation.