UK Vintage Radio Repair and Restoration Discussion Forum - View Single Post - Ampro New Educational

EF80TVVALVE · 17th Dec 2022, 4:16 pm

I've managed to get the motor out of the projector now and gave it a closer inspection. All of the windings look to be in excellent condition, there are absolutely no signs of overheating or burning which I was expecting. One thing I have found is that there are trenches between each contact of the commutator, on a lot of motors I encounter this is often filled with plastic or other material to give a completely smooth surface. As you can imagine each of these was caked full of old carbon deposits, I have cleaned this all out along with the rest of the motor and regreased. I am still in the middle of finishing off to refit so I hope that this has cured the problem and that it was due to tracking along the commutator contacts from all of the built up carbon.

Just a heads up, these motors are absolutely horrid to strip and clean! One of those where once the two main screws are out everything becomes loose and starts falling apart, it requires a lot of care to re-assemble with everything just in the right place as you begin to screw it all back up.

17th Dec 2022, 4:16 pm	#14
EF80TVVALVE Octode Join Date: Feb 2010 Location: Leicester, UK. Posts: 1,433	Re: Ampro New Educational - motor woes, issues and solutions I've managed to get the motor out of the projector now and gave it a closer inspection. All of the windings look to be in excellent condition, there are absolutely no signs of overheating or burning which I was expecting. One thing I have found is that there are trenches between each contact of the commutator, on a lot of motors I encounter this is often filled with plastic or other material to give a completely smooth surface. As you can imagine each of these was caked full of old carbon deposits, I have cleaned this all out along with the rest of the motor and regreased. I am still in the middle of finishing off to refit so I hope that this has cured the problem and that it was due to tracking along the commutator contacts from all of the built up carbon. Just a heads up, these motors are absolutely horrid to strip and clean! One of those where once the two main screws are out everything becomes loose and starts falling apart, it requires a lot of care to re-assemble with everything just in the right place as you begin to screw it all back up.