DEC BA11-K noisy fans

[Fritz Mueller]

Hi all,

I've been working on a BA11-K PDP-11/34 lately, and wow it sure is a noisy thing...

On my '11/45, the "Boxer" fans were easily disassembled via a cir-clip, and could then have their bearings cleaned/relubed (or worst case replaced).  Fan maintenance quieted down the /45 a good bit.  But these larger 6" Amphenol units don't look quite as easy to get in to...

Is the plastic rotor on these just a press fit?  Any tricks to getting in there for maintenance?  Or are these "you have what you have" and the only option if unsatisfied with their current performance to replace them entirely?

   cheers,
     --FritzM.