Enco Mill - motor takes a few tries to get to full speed

[talvare]

From your initial description of the problem, it sounds like you likely have a sticking, dirty or defective centrifugal switch. This is a pretty common problem on capacitor start motors. Many times it can be resolved just by removing the motor end bell and cleaning the switch mechanism. Just some food for thought.

Ted

 

[tcweb]

Ted, I will (reluctantly) take the motor off and see if I can get it apart...

Tom

 

[Chris Hamel]

I have an enco gl 30 b built in 1972. It definitely has a centrifugal switch. I can hear it. Something to check on the mill in question would be to listen for the switch. It you don't hear it at startup, you should definitely hear it when the motor slows down. If it is sticking on, it would cause all kinds of trouble. The start windings pull a lot of current.

 

[tcweb]

OK, I have the new caps, and the motor is on my bench. Warming up. It's freaking 5 degrees (F) here.

My next challenge - getting the pulley off the motor. Looks like two set screws at 90 deg to each other. 3mm hex, seems to be close fit. They are TIGHT. Any tips for getting them out? I have them soaking in penetrating fluid right now. Even with the set screws out, my guess is that the aluminum pulley is not going to want to just slide off the motor shaft.

Any tips for not damaging the pulley? Or the motor shaft? Use wedges to try to force it off?

-Tom

 

[Tozguy]

It's freaking 5 degrees (F) here.

Cool is kewl, less chance of things overheating

The motor pulley should have a keyway. Set screws should only be to keep the pulley aligned. Once the screws are loose the pulley should slide OK. I'd use a puller if the shaft is rusted or the pulley is seized with crud.

 

[tcweb]

Got the set screws out! Soaking in penetrant overnight and some very light heat with a micro torch.

Damn pulley is still stuck tight to shaft.

Can’t see how to use a puller, since the end of the step pulley is not open.

Tom

 

[Tozguy]

Huummm, too bad that it is so uncooperative!

Would tapping on the end of the pulley be worth a try?
Vibration might break the bond then maybe it could be worked back more easily.
As the man said, if it went on then it can come off. Sounds like a job for a puller of some kind.

since the end of the step pulley is not open.

Drill and tap the end of the pulley for a draw bolt? Can we have some pics of the pulley?

 

[tcweb]

I will send some pics. I may try tapping it with a dead blow hammer, just to see if they key loosens up.

 

[Mark Needham]

"dead blow hammer" be damned. Get an axe, and whop the muther.

 

[tcweb]

Here are the pictures of the pulley.