I had one of these for a number of years. Completely dissassembled and re-assembled it several times to make sure it was all working correctly. They are technically not that difficult a unit to play with and surprisingly well designed. I unfortunately dont have it now, sold it a while back, someone else on here does....
But I think you will find that if the motors are going, and you can hear them, you will find it will track no problems at all (once you put it together properly). Mine always made an unpleasant sound while the motors were going, I think its just how they are, and as they are a completely sealed motor there is little you can do to change that.
You may have a problem with how you put it together... From memory, basically the motors drive directly onto a large toothed wheel (say 8" across), this wheel is attached onto the drive plate, the forks only lock onto the drive plate if the RA lock is engaged, so you need to be careful not to get greese on the lock or drive plate, and the lock may need adjusting to get the correct right height. This is done by removing the knob on the RA lock and screwing it in or out to get the right height and then re-attaching the knob.
The setting circles do nothing, and are near useless (IMHO). The large spring you spoke of simply adds a bit of tension into the setting circle plate to allow it to spin, but not too freely... If memory serves it goes between the setting circle plate and the drive plate (or maybe its the other way around, its fairly obvious anyway).
The other thing to watch is to make sure the gears from the motor are actually engaging on the drive ring. The motors can be moved in their housing, and made to do so, so you need to set them to sit on the drive ring, if you have removed the motors from the bottom half of the unit, and put them back you may not have them in exactly the right spot, hence not engaging. This is an easy mistake, and one I had to deal with. The idea is to get both motors engaging the ring equally so that one is not taking more load than the other. You will hear the motors take up the load if they are engaged.
Finally yes, its a slow moving setup, dont expect to see anything occuring visually. Easiest way to test if its working or not is to point it at a land object at high power, and see if the object starts to drift when the motor is on. You dont need to wait until night to see that.
The dec adjustment is also fun to play with, and can take some getting right.
Mine was surprisingly accurate, and could track objects for quite some time without adjustment (even with crappy polar alignment).
Pulled it apart today. Two internal screws had fallen out! Perhaps I never tightened them last time, but they do only catch by a few threads. Replaced and tightened all three, rebuilt, adjusted the Az clutch so it locked more surely, and tested the motor drive. OK, seems it is all working now. If these clouds clear a little, I'll check it out on the stars tonight. I recently cleaned the secondary and primary mirrors. Not by the textbook - I tapped the corrector plate mounting and popped the whole lot off! OK, no problem, I could get at the mirors so a gentle wash etc. Forced the corector plate mount back over the tube and firmly forced back into place - seems very secure but I must watch it as the scope heats and cools. So I expect collimation to be way out now.
Umm, I hate to ask, but I assume you got it back into the same holes?
The corrector plate and mirror are aligned, if you didnt get it back into the same holes then it will never align properly and probably always be out of focus.
The nice thing with these scopes is that these are no optical coatings, so you dont need to be as concerned with washing them away etc etc.
I had marked the upper mounting and the tube before I started and have replaced the mounting back at the same location. No choice -I needed to get the adhesive I had broken to match up again to get it on!
Have looked during the day and everything looks fine - image and focussing. Just waiting for even one star to show itself so I can see how the collimation is - clouded out for days now. About time I built myself an artificial star.
I"m a bit late to this thread, but hopefully someone can help me?
I have a "Northern Hemisphere" Orange Tube C8, which I want to
take to Brazil with me.
Voltage and Frequency are compatible (and in any event, I run
it off of a home built Drive Corrector.)
Does anybody know what wiring changes need to be made
to get it to track in the opposite direction for Southern Hemisphere
use? (I can live with the setting circles being wrong.)
I have an orange tube Celestron 8 that came from the US in the '70s. My brother is an aircraft engineer and had a look at the motors. His verdict is that the motors cannot be reversed by rewiring and it would have to be a mechanical change. So it's not easily done at all I'm afraid.
I still have mine Philip. It's still useful as a public viewing/"grab and go" scope. It's done some travels - northern hemisphere for five years. Here it is shooting a building across a wide bay in 2015
