Oil filling cup preassembling tool

The utility model relates to a preassembling tool for an oil filling cup. The preassembling tool comprises a base, the first clamping mechanism is mounted on the base, and the first clamping mechanism is provided with a first accommodating space of which the size can be adjusted; the second clamping mechanism is provided with a second containing hole with the adjustable size. The third clamping mechanism is installed on the bottom plate, the third clamping mechanism is provided with a third containing hole with the adjustable size, the bottom plate is arranged on the base in a sliding fit mode so that the bottom plate can get close to or get away from the second clamping mechanism, and the extending direction of the axis of the third containing hole is the same as the extending direction of the second containing hole; the base is provided with a third containing hole, the axial positioning mechanism is installed on the bottom plate and provided with a feeding push head, the push head is used for locking the a