Abstract: A chisel for rotationally disengaging a threaded bolt, nut or screw, has at one end thereof a cutting edge for cutting into and penetrating a surface of the bolt. The chisel further includes a first chisel face terminating at the cutting edge of the chisel, and a stop face positioned away from the cutting edge with the first chisel face disposed between the stop face and the cutting edge. The stop face is at an angle of about 90 degrees or less with respect to the first chisel face. The cutting edge has a width that is about equal to or greater than the distance between the stop face and the cutting edge. The stop face prevents further penetration of the cutting edge into the bolt beyond the stop face so as to provide for application of rotational force to the bolt by the chisel without further penetration of the cutting edge into the bolt.

Abstract: Method and apparatus for changing oil in an internal combustion engine pierces an outer wall of an old oil filter containing old motor oil to form an opening in a lower portion of the filter wall. Old motor oil is drawn from the pierced oil filter into a container by suction through the filter wall opening and a suction conduit. The oil drain plug from a crankcase containing old motor oil is removed to form a drain opening in the crankcase, and old motor oil is drawn from the crankcase into a container by suction through the drain opening and a suction cup, to empty the crankcase of old motor oil. The drain opening is closed after emptying the crankcase of old motor oil by securing the drain plug in the drain opening. The pierced and drained old oil filter is replaced with a new filter and the drained crankcase is refilled with fresh motor oil.

Abstract: A drain plug removing device includes a clip for rotatably engaging and selectively holding a head of a threaded drain plug. The clip has an axis of rotation and includes a pair of openable jaws urged together by a spring. The device includes a selectively bendable, flexible shaft attached to the clip at one end thereof, the shaft being formed of a reboundable coil spring extending away from the clip along the axis of rotation of the clip when the shaft is in an unflexed configuration. The shaft has a handle at another end thereof opposite the clip, such that rotation of the handle applies rotational force to the shaft, which in turn applies rotational force to the clip to cause rotation of the clip and a drain plug held therein. A drain plug can be removed from a crankcase oil pan with the device of the invention without spilling oil onto the fingers and without dropping the plug into a drainage catch basin or funnel beneath the oil pan.

Abstract: A drain plug removing device includes a rotatable socket for engaging and selectively holding a head of a drain plug. One end of a flexible line is connected to the rotatable socket, and the other end of the line is secured to a support to prevent the socket and drain plug from falling further than the length of the line if dropped and to support the line and the socket holding the drain plug. A method for removing a threaded drain plug from a collection pan includes the steps of engaging a rotatable socket with a head of a drain plug, the socket having a line connected thereto, securing an end of the line opposite the socket to a support, and rotating the socket to remove the drain plug.

Abstract: A hydraulic control valve for a single-acting cylinder includes a valve housing having a cylindrical valve bore. A supply port present in the valve housing is in communication with the valve bore, as is a discharge port and a delivery port. A valve pin is slidable within the valve bore between first and second pin positions, the valve pin including a pin groove positionable to establish communication at the first pin position between the supply port and the delivery port to the exclusion of the discharge port. The pin is slidable from the first position to the second position to establish simultaneous communication with the pin groove between the supply port, the discharge port and the delivery port.

Abstract: Method and apparatus for changing oil in an internal combustion engine pierces an outer wall of an old oil filter containing old motor oil to form an opening in a lower portion of the filter wall. Old motor oil is drawn from the pierced oil filter into a container by suction through the filter wall opening and a suction conduit. The oil drain plug from a crankcase containing old motor oil is removed to form a drain opening in the crankcase, and old motor oil is drawn from the crankcase into a container by suction through the drain opening and a suction cup, to empty the crankcase of old motor oil. The drain opening is closed after emptying the crankcase of old motor oil by securing the drain plug in the drain opening. The pierced and drained old oil filter is replaced with a new filter and the drained crankcase is refilled with fresh motor oil.

Abstract: The biting edges of a toothed bit are forced into a damaged bolt or the like and rotated by operation of an impact wrench coupled to the toothed bit to rotationally disengage and extract the damaged bolt.

Abstract: A hydraulic control valve having a valve housing including a cylindrical valve bore, the valve bore being in communication with a supply port, a discharge port and first and second delivery ports each with first and second openings to the valve bore. A valve pin is slidable within the valve bore, the valve pin including first and second pin grooves operable to establish communication between the supply port and either of the delivery ports to the exclusion of the other delivery port, the supply port and discharge port communication being establishable through corresponding valve bore openings of respective delivery ports. Supply port communication with one of the delivery ports is establishable simultaneously with discharge port communication with the other delivery port.