I have a very old house, built in April of 1952. we found out when we removed the kitchen floor and found they had used some newspaper as part of the vapor barrier. but anyway the siding is the old style asbestos shingle, the one with the Wave bottom. I have tried painting with latex and enamel. both seem to peel in a year or two.
is there a primer made just for this type of application.
I would recommend power washing to remove all the chalk and loose paint then full prime with ICI Gripper. that should hold you for 2 to 5 years. you can not expect much longer than that on previously painted exteriors.