The scraper front air brake actuator, NSN 2530-01-415-2558, that’s shown as Item 15 in Fig 94 of TM 5-3805-296-24P (Jun 13) doesn’t break down into individual parts.
Problem is, wear and tear during construction causes the actuator—particularly its boot—to get banged up and torn apart. The boot’s rubber also dries out and becomes cracked. Eventually, the boot breaks off, leaving the actuator’s brake cylinder rod exposed to the elements. Not good!
Until the actuator’s boot becomes available separately, order the 621B scraper boot that costs $21.42 with NSN 2530-01-065-9106. It’ll work on the 621G scraper!
By the way, ordering this boot is a big cost savings when you consider that an actuator assembly costs over $258 bucks!