Jobo CPA-2 Motor Dead

[twelvetone12]

Hi All,
(there was a url link here which no longer exists) while I was developing some color film my CPA2 motor stopped working.
The machine is a historic unit that I found in my shared darkroom and we restored it to functionality, or at least I thought.
Basically what happened is that mid-developing of a roll (the first roll of the session) the motor just stopped. The speed was "P". If I gently pushed the tank it would start again to move, but veeery slowly. When turned on and off you could hear the relais inside clicking. It was also not the inversion fingers as I moved those various times. The motor really just seemed stuck. I'm going to check the fuse but I don't think it is blown.
After a couple moments that it stopped turning I turned off the motor and continued by hand.
How can I start troubleshooting the motor? I could not find any repair manual nor schematics for this unit. Can anyone share any tips on how to start?
Thanks!

 

[Anon Ymous]

I can't say for sure, but there might be a capacitor blown in there. Electric motors typically have a starter capacitor.

 

[twelvetone12]

Yeah I found another thread were they suggested recapping the thing, but I'm still looking for the schematic to help me figure out if there is something else blown. Also hoping it is not a mechanical problem.

 

[AgX]

I can't say for sure, but there might be a capacitor blown in there. Electric motors typically have a starter capacitor.

The motor we are talking about is a low voltage DC motor. No capacitator aside maybe for emssion protection.

I would also check the relay that controls that motor.

 

[ic-racer]

(there was a url link here which no longer exists)

 

[John Koehrer]

I haven't read the above link but recall some wiper motors can be swapped out,

 

[Andrew K]

I have a cog lid that won't work on either of my Jobo's with the lift fitted - it causes the drum to intermittently jam.

I swapped lids and it's all good again

I also found my lift is worn and does not "lock" correctly to the head, so I have to clamp it into place. I've done this for a few years now and have no problems developing 8 rolls at a time

 

[Sirius Glass]

You can get help from Dave Smith aka http://www.darkroomdoctor.com/ also a board member of FreeStyle.

 

[twelvetone12]

I FINALLY got around working on the electronics of the jobo. I attached the motor to a power supply and it works perfectly smooth, sucking just 200mA. If I bypass the transformer and run it on the ext power supply it uses c.a. 240mA, which seems reasonable to me, but I would need to test that under load to see if it gets too high.
It seems the fuse connector was faulty - I changed that with a better one and the Jobo seems to run well now. But I'm not completely convinced: when running the TIP 3055 motor driver runs HOT, so hot that you can feel the warm plastic when the enclosure is in place. The 3055 is rated 15A, is this normal?
Also I'm scratching my head on the fuse: the schematic says 800mA, while the manual 1.25A. Which one is right? My jobo is very old, the electronics are "old style" as the repair manual states, but it is still a bit puzzling.

I also have a question: is it possible to re-grease the gearbox? After almost 40 years of life the grease that leaked outside seems just a sticky mess.
Thanks!