Jaw spring Bronze clutch plates Planetary gear Planetary carrying arm Jaw engaging spline Sun gear shaft extension  and jaw stop retainer nut Return spring Starter jaw Conical clutch suface Traveling nut Sun gear Steel clutch Clutch spring retainer Internal gear Motor pinion Motor shaft Intermediate countershaft Countershaft pinion Figure 5-6.  Starter gear section.  enough to relieve some of the spring pressure on the conical  clutch surfaces. As long as the starter continues to rotate,  there is just enough pressure on the conical clutch surfaces  to provide torque on the spiral splines that balance most of  the pressure of the jaw spring. If the engine fails to start,  the starter jaw does not retract since the starter mechanism  provides no retracting force. However, when the engine  fires and the engine jaw overruns the starter jaw, the sloping  ramps of the jaw teeth force the starter jaw into the starter  against the jaw spring pressure. This disengages the conical  clutch surfaces entirely, and the jaw spring pressure forces  the traveling nut to slide in along the spiral splines until the  conical clutch surfaces are again in contact. Being splined in this fashion, rotation of the shaft forces  the nut out and the nut carries the jaw with it. A jaw spring  around the traveling nut carries the jaw with the nut and  tends to keep a conical clutch surface around the inner wall  of the jaw head seated against a similar surface around the  underside of the nut head. A return spring is installed on the  sun gear shaft extension between a shoulder, formed by the  splines around the inner wall of the traveling nut, and a jaw  stop retaining nut on the end of the shaft. Because the conical  clutch surfaces of the traveling nut and the starter jaw are  engaged by jaw spring pressure, the two parts tend to rotate  at the same speed. However, the sun gear shaft extension  turns six times faster than the jaw. The spiral splines on it  are cut left hand, and the sun gear shaft extension, turning to  the right in relation to the jaw, forces the traveling nut and  the jaw out from the starter its full travel (about  5 ⁄ 16  inches)  in approximately 12° of rotation of the jaw. The jaw moves out until it is stopped either by engagement  with the engine or by the jaw stop retaining nut. The travel nut  continues to move slightly beyond the limit of jaw travel, just  When the starter and engine are both running, there is an  engaging force keeping the jaws in contact that continue  until the starter is de-energized. However, the rapidly moving  engine jaw teeth, striking the slowly moving starter jaw teeth,  hold the starter jaw disengaged. As soon as the starter comes  to rest, the engaging force is removed, and the small return  5-5