Topic: belt slipping / faulty motor

[nooner]

Hi, I've now found a new problem.  I've "improvised" a battery, using a jump starter, but as I tried to move off in the back garden, I had a horrible clicking noise.  At first I thought it might be a torque limiter, or worse the gearbox falling apart, but it seemed to be the drive belt slipping as it had jumped off a few times.

Problem now is the motor isn't spinning, or even making any noise.  The relay clicks, the motor freewheels and I get 12.4V across the brush wires (the large red & black wires in the aluminium) but no motion.  does this mean my brushes have burned out?  I'm meaning to write an introduction about my situation etc but haven't got round to it yet.

Cheers

[radiomarty]

Hi Nooner - If you are measuring 12v at the red and black leads motor end when the button is pressed then I think you need to take the motor apart to check on the brushes - if OK possibly clean the armature also check for any damage ie broken shaft etc - link included on how to do this etc


http://c5alive.co.uk/forum/index.php?topic=368.msg2474#msg2474

Keep us posted on findings - once you cure the motor we can work on the belt slip

Regards Radiomarty

[nooner]

Had a little fiddle today, managed to get the motor rotating slowly.  The rotor is/was corroded, all black.  Tried cleaning it up with a bit of Scotchbrite in-situ, but hasn't worked.

I'm going to try the brushes, but the manual says about pulling the brushes out through the brush housing.  Should they appear ok, can they then be re-used?  Also, what is the minimum effective thickness?  I mean, they could have been replaced, but not fitted correctly.  I don't want to fork out £20 for something that I don't need!

[nooner]

Just a quick update.  I decided to strip the motor down.  I couldn't pull the brushes from the housing, as I couldn't find my mole grips so I wasn't too bothered about damaging them: after all, they were knackered anyway....
      As the housing came apart (I left the gearbox on), one of the brushes popped out to about an inch proud, the other about 1/4".  Only one was gone, I thought.  As I poked and prodded the second shot out, almost meeting in the middle.  It seems like I had a seized brush; it would explain the low torque, high load reading and stuttering performance.  Using a bit of Scotch-brite I cleaned the rotor contact up, and applied, what in hindsight might have been a silly idea, a wee bit of Coppaslip to the side of the brushes.   I reassembled the motor, refitted it to the "Motah", rejoined the cable as I had to cut it, and it sounded like a perfect condition motor would.  To keep the brushes out of the way during reassembly, I duck-taped them back, slid the rotor in and pulled out the tape (thanks to the Coppaslip it didn't stick to the face of the brushes)

The Drive belt is still slipping, I'm not sure which way I twist the motor to add tension.  I've tried shimming it with an old bank card but it still slipped.  I've marked up a groove on the output gear, and it is definitely spinning, so the horrible crunching noise is coming from the belt, not the gearbox.  If I can't shim it enough then I'll price up a new belt: there is a BSL trade counter not too far from me.

[radiomarty]

Hi Nooner - glad you sorted the motor problem without too much stress - motor slip is also a common issue than can normally be solved with a cable tie or mod bracket - try this thread let us know if it works :
http://c5alive.co.uk/forum/index.php?topic=713.0

[C5 ENTHUSIAST + RESTORER]

Hi there Nooner just check out this ..

Just thought I'd upload a photo of the motor support bracket in place as you can see the bracket keeps the lip in place ...or as it has been said you can use a tie wrap

[nooner]

I think I've sorted the slip; when I tried adjusting the tension I had inadvertently moved the motor from the support bracket....Ooops!

Wiggled it back on, tightened it, and wrapped a cable tie round the back end of the motor/rear axle, to stop it tilting, and it seems to have done the trick.

Is that strip of copper a proper support or a bodge job?  It wouldn't surprise me one bit that being an "authorised Sinclair modification!"  Mine is still just the original plastic.

Thanks for all your help, I'm going to hang around on this forum because you all semm like you know what you're on about!

Cheers!

[C5 ENTHUSIAST + RESTORER]

Hi there the support bracket is not copper ,it's spring steel and it is an authorised Sinclair modification...
Not many left but a tiewrap will do the same job , just a little harder to fit

[Karl]

Thanks for all your help, I'm going to hang around on this forum because you all semm like you know what you're on about!

Cheers!

..we try our best 

Glad to hear the c5alive forum is helping to keep another c5 on the road