[GreenKeys] Model 28 clean and lubricate

[Harold Hallikainen]

I got my first look inside a model 28 yesterday as I try to help Mike (
KD7VRG ) get his 28 running.

It looks like one or two bits on the receive side are stuck. It prints Y
correctly, but not R. Also, it will not go to LTRS, just stuck in figs.

Looking at the right side of the printer, I see one code bar that seems to
move into place late, like it's gummed up and moving more slowly than the
others. Though the printer looks pretty clean, I suspect that it needs
cleaning and lubrication.

On my model 15, I have been using Valvoline Full Synthetic Advanced SAE
0W-20 oil (UPC 7413000916) and Permatex White Lithium Grease # 80345. Do
these seem appropriate for the 28?

I cleaned my 15 with Simple Green, largely soaking it and wiping the crud
off but trying not go get the selector magnets wet. Is that appropriate
for the 28?

Once the printer (especially the typing unit) is clean and dry, I find the
lubrication instructions at
https://www.navy-radio.com/manuals/tty/217B-5903.pdf#page=169 .

Does this sound about right? I think the machine is very close to
operating properly but just has some sticky parts.

Thanks!

Harold
https://w6iwi.org