END PLATE

1 Brushes and bushes

The end plate houses the carbon brushes. These pass the current from the supply wires to the commutator. Recessed into the centre of the plate is the spherical bush in which the spindle runs.

2 Check brush length

Degrease the brush area with an artist’s brush and solvent. Keep the solvent out of the bush. Trial-fit the commutator to see how much length is left in the brushes. They’re usually barely-worn.

3 Oil bush

Lubricate the bush by oiling the felt ring around it. Use a light lubricant such as sewing machine or air-tool oil. The tidiest way to add oil through the small holes is with an artist’s brush.