I pulled a card and couldn't insert it into the backplane reliably, so when I inspected I found that two pins were bent. The plastic cover over the card end had cracked and had other damage that led to this. While I bent them back correctly to the eye, cards still won't snap in. This will be fun, I can see.
I will continue to adjust the pins and work on getting the card to seat properly. I replaced the plastic cover from a spare SLT card, manually marking the card number. Hopefully I will get everything repaired.
FINALLY REMOVED BLOWER CAGE FROM MOTOR SHAFT
The blower motor which produces the high volume of air through a HEPA level filter to float the recording heads over the disk platter was not working. I identified that one of the wires to the motor was an open circuit. Dismounting the motor from the drive was easy, but the blower cage and rotor was almost welded to the motor shaft.
The removal of the setscrew should have allowed the rotor to slide off, but it was almost beyond my ability to get it off. Since the hub was inside the rotor cage, a traditional pulley would not fit inside. I had to partially disassemble the motor to be able to put enough torque on the shaft to help dislodge it.
I had to scrape some corrosion off the end of the shaft and use clock oil in order to get it to move better. Finally with some vice grips on the hub and lots of effort, I got the shaft to come out. Now the motor needs to be repaired or replaced.
LOOKING FOR EASY FIX FIRST
I was hoping that I had a break in the wires, as they were shielded inside woven metal and an outer plastic cover. Alas, I confirmed that the break is inside the motor. All my inspections failed to uncover an obvious point of the failure, thus there is no hope of a surgical fix.
THINK I FOUND A CLOSE MATCH ON EBAY TO REPLACE THE DEAD MOTOR
The motor was built by Robbins & Myer. The data plate show that it is a single phase motor, 1/30 horsepower, turning at 3450 RPM. The frame type is F26 which indicates the physical dimensions of the motor and shaft.
I looked on eBay and found a very similar motor advertised. It is the same frame type F26, spins at 3350 RPM which is close enough as this only moves air. The other difference I see is the type is KP whereas the disk drive motor is KS. I suspect the difference in speed is the reason the type varies.
According to the listing, this was pulled from a Bell & Howell 16mm projector, but is working. It appears to be a nice drop in replacement and I should receive it within the week.
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