Twin Sonic issue.

[jdh]

I restored a twinsonic recently that I am going to sell. The thing is, when I first power it up, it runs for about a minute, then the motor slows down for about 30 seconds, then slowly starts speeding back up again. Other then that, it runs smoothly. If I shut it down for 5 minutes, it does the same thing.

It has to be the motor, and it does this on both a strong battery and/or a good power supply every time I have tested it.

What would cause this???

 

[Stampeed Valkyrie]

Could need to be cleaned out or an issue with the brushes. What kind of motor is in it?

 

[jdh]

Could need to be cleaned out or an issue with the brushes. What kind of motor is in it?

Ill need to take a snap shot, but it is the original motor.

 

[jdh]

This is the exact same motor. I am trying to rebuild this one b/c it seams the barrings are seized up..

 

[Stampeed Valkyrie]

ok Type 2 motor. Let's get @Skulldigger in here. See if he can drop some hints.
I probably would give it a clean out with the electrical contact cleaner at the minimum to see if that frees up any carbon and gunk in the motor.

 

[Skulldigger]

It can be the motor but it can also be something as simple as you have to much contacts pressure between the motor gear and the light gear. If the light's gear is slightly worn out of shape and the gears are pressed to tight against each other you get that alternating slowing. The best way to determine if it is the motor is to take it out and power it up. Grab the gear and see how much resistance it takes to stop the motor. If it is easy to stop, it's the motor. If it's the motor I'd be glad to take a look at it.

I am trying to rebuild this one b/c it seams the barrings are seized up..

Careful with that fiber card that holds the brushes. They get brittle. I do fabricate them but have to have the motor to do it, as it is a precise fit. To loosen those bearings, put oil in through the weeping hole and using a small screw driver move those bearings around to work them free.

 

[jdh]

Good day Skulldigger.

The motor that I showed you, opened and closed very well and I did get it working. Thanks for the tip.
As for the twin. I rebuilt it from scratch. So I was very attentive to the gear box for the motor and the bulb carousels. I made sure the tension was correct. I have rebuilt many twins, areo twins and jets, to know how the chain works. This is why I suspected the motor. However, I have never had a chain/belt bar slow down after a minute then slowly speed back up. The thing is, once it spead back up, it stayed constant.
Weird