Advice about servicing Crank Handle Mechanism on skylight, please.

[Revolvor]

The crank handle mechanisms on my two skylights have become stiff, and difficult to operate .

I can remove the lid from the gearbox and lubricate the internals, but have not found a way to get lubricant into the horizontal tube/cable part of the mechanism.

Please can anyone suggest how to free up and lubricate the mechanism, and also advise any long-term maintenance?

 

[Revolvor]

My memory seems to have failed me. I was sure that there was a lid to the gearbox, but that doesn't seem to be the case.
The cables run in curved metal tubes, but there are straight, flexible plastic tubes coming out of the gearbox too. Could I just cut the tie-wrap, flex it upwards and introduce lubricant that way?

 

[2bob]

can you not drill a small hole in it then spray some silcone
it in

 

[Landy Andy]

I would think the tightness is in the bent metal tubes where the cable moves. You can get spray lubricants that are very thin, but then thicken as they dry. Wurth do a few types that I use.