Startrite Mercury Pillar Drill - no power

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biker_smith

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Hi all,
I bought this drill a few months ago and soon after I started using it I noticed its lack of power. It stalls out under very little load (my drilling is mainly metal work - not wood) and I can stall the chuck just by gripping it with my hand. Today I've removed the motor with the intention of checking it out to see if anything obvious is causing the issue - I have it mounted in my vice and can spin it up, but the same issue very low torque and easily stopped using the pulley.
So my question is please - is the motor shot, anything I can do to fix it? If not can I get a replacement motor or get this one fixed?
Many thanks for your help - Paul.
Many than
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That seems a pathetically low power motor for a drill press. Although the paint job looks the same colour but I wonder if it has been added later.
What power motor does the manual suggest it should have?
 
Hi - thanks for the input - the motor has been sprayed, so may not be the original. I have an info sheet (attached) that shows 0.66 HP.
From your document link 0.25kW is about 1/3 HP so this motor is only a third of the power of the motor that should be fitted.
So it sounds like I need a replacement motor of the correct 0.66 HP (or more) - do you know a supplier of the correct type that will fit the mounting points on the drill?
Thanks again - Paul.
 

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  • Drill spec sheet.pdf
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My Startrite Bantam (same head as the mercury) has a 1/2 HP motor, which is an original Ranco. See here:
https://www.ukworkshop.co.uk/threads/startrite-bantam-drill-refurb.123627/
Your motor is quite different, but from the state of the drill, it looks like yours is a bit newer.
In any case, unless it's just your belt slipping (have you checked?) it sounds like your motor is knackered.
 
Hi - thanks for the input - the motor has been sprayed, so may not be the original. I have an info sheet (attached) that shows 0.66 HP.
From your document link 0.25kW is about 1/3 HP so this motor is only a third of the power of the motor that should be fitted.
So it sounds like I need a replacement motor of the correct 0.66 HP (or more) - do you know a supplier of the correct type that will fit the mounting points on the drill?
Thanks again - Paul.
i'm confused, is 0.66 hp not 2/3 hp? so your motor is half the power not a third, or have i missed something in the rating??
 
The drill looks like it's in great condition - maybe come out of a school workshop? Possible they downgraded the motor so the kids would find it harder to injure themselves?
 
Yes it came from a school - it has a sticker on the side.
So I've learnt two things from your posts - my motor is half the HP is should be and it also may well be worn out.
So - can I just buy a new one of the correct spec HP, is there a supplier in the UK?
Thanks - Paul.
 
I have a Mercury and I am pretty certain it still has the original motor on it. I will take a look at it when i get home this evening and see what the Wattage/HP of the motor is. The motor on mine certainly does not look like that AEG motor in your pictures.....I think mine is a Brook Compton motor..???

My drill is partially dismantled at the moment for refurbishment, so the motor has been removed....
 
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Hi - thanks for the input - the motor has been sprayed, so may not be the original. I have an info sheet (attached) that shows 0.66 HP.
From your document link 0.25kW is about 1/3 HP so this motor is only a third of the power of the motor that should be fitted.
So it sounds like I need a replacement motor of the correct 0.66 HP (or more) - do you know a supplier of the correct type that will fit the mounting points on the drill?
Thanks again - Paul.
Hi check out Solent rewinding in hilsea portsmouth the have a great reputation locally a small family run business and not to far from you
 
I don't think it has a capacitor.
If it's equivalent to the earlier motors it will be split phase/resistance start.
It's possible the centrifugal switch is stuck. It should be possible to take the bottom off and check.
 
I don't think it has a capacitor.
If it's equivalent to the earlier motors it will be split phase/resistance start.
It's possible the centrifugal switch is stuck. It should be possible to take the bottom off and check.

There looks as though there is a capacitor in the picture of Biker Smiths motor..?
 
A failed capacitor would normally stop it from starting up in the first place, but certainly worth checking.

Are you absolutely sure the motor fully stalls, and the shaft isn’t spinning inside the pulley? (Egg-sucking disclaimer).

Low torque when running is an unusual fault, as this type of motor runs exclusively on the ‘run’ winding. How many wires come from the capacitor? It’s just possible that it’s a two-part one, with both parts used to start, then one part used to improve running torque. Can you take a picture of the markings on the capacitor (underneath the helpfully applied paint)?

If you start and stop the motor, can you hear a click as it comes to a stop?

Edit: I have had a cheapo drill press for 20 years, rated 180W, and it has enough torque to drill 13mmm holes in 4mm steel (just), so what’s described here is certainly a fault.
 
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I've taken a photo of the capacitor.
Yes it is the motor stalling, not the shaft turning in the pulley or the belt slipping - I have it in a vice now so no belt being used to test.
There is no clicking on start or stop.
Thanks - Paul.
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