Pillar drill 240W motor not starting/spinning, just hums

[fuzzytrifle]

I've got a small 240v pillar drill with a 550W motor. It's getting on a bit but has been very reliable until recently - every now and then the motor doesn't turn and just hums, spinning the chuck by hand gets it going, but isn't exactly safe.

Is this due to a worn capacitor, or will I have to replace the entire motor?

 

[AllowAllGarages]

Does sound like the cap if hand spinning gets it going.

 

[matt1e]

Does sound like the cap if hand spinning gets it going.

I concur it will be the cap, or a problem with the auxiliary winding (cap more than likely)

Matt

 

[SimonH2]

If it's getting on a bit it might have a switched start winding - in which case it could also be a dicky centrifugal switch.

 

[fuzzytrifle]

Thanks for the replies. I was just wondering if it was more than a worn capacitor due to the random way that it's been starting - I used it for most of this afternoon and at a guess I'd say that it started normally roughly half of the time, occasionally it stuttered before getting going, and sometimes needed more than one spin by hand.

I'll have a look for a replacement capacitor - it has to be worth a go before forking out for a new motor!

 

[SimonH2]

There is probably a wiring diagram inside the terminal box, a photo of that and/or the terminals and wiring might reveal additional information.

 

[bernardgreen]

If the starting is stuttering then I would go with Simon's suggestion of a worn centrifugal starting switch.

A defective capacitor would result in consistant poor starting and would be un-likely to make the motor stutter as it started.

 

[ericmark]

Since intermittent I would not expect the capacitor but something connecting the capacitor. There are a number of methods already mentioned is centrifugal switch. There are also timers but mainly that type are used with pumps. Even possible as part of start switch.

 

[ricicle]

Once the connections are checked it is probably easier and cheaper to rule out the capacitor with a new one as this is what it turned out to be on one of our hydraulic cardboard compactors when it suffered from erratic starting.

 

[fuzzytrifle]

Connections checked and everything seems ok. Trying a replacement capacitor would definitely be the easiest option as I don't really fancy removing and dismantling the motor - problems with the centrifugal switch sounds terminal - at this rate it will probably end up on ebay for spares!