How do I remove the carbon brush holders from my HD 77 Skil saw?
It is not quite clear to me why you want to remove the brush holders. Normally the brush replacement does not require much saw dis-assembly at all. You simply remove the cap part (item #46) and remove and replace the brush.



From looking at the exploded parts diagram it appears that the brush holder (item #50) is simply press fit in place and secured with the set screw (item #56). The brush holder does appear to have a notch on the edge for aligning the holder to the proper orientation in its seating in the cast housing. So it is very likely that the holder must be removed by pulling it straight out.



Before removal of the brush holder it would be necessary to understand how the electrical wire connections to the motor assembly connect to the holder and disengage that connection. Those connections are circled in red above.

If the brush holder is not able to be freely pulled out because it is siezed into the casting seat it may be necessary to make a tool to assist in working it loose. This could be done by making a hardwood stick that has a cross sectional dimension that matches that of the brush. A stick that was six or eight inches long could be inserted into the holder from the outside and used to apply some side to side rocking force on the holder to work it loose.