Drill Press Motor Repair Help

i was able to bring the capacitor up to work and measure it. it says 400-440 MFD on the side. we deduced that actually means 400-440 mFD. it measures in the nFD range. The terminals are not dead shorted to each other. So i guess the capacitor is bad?

the wires the hook to the capacitor measure 4 ohms without the capacitor hooked up as you guys predicted.

Is there anything else i can check before I buy a capacitor? Am i right in thinking that if the capacitor is the only thing wrong, then it probably should have started with the pull cord?
 
Tutt said:
i was able to bring the capacitor up to work and measure it. it says 400-440 MFD on the side. we deduced that actually means 400-440 mFD. it measures in the nFD range. The terminals are not dead shorted to each other. So i guess the capacitor is bad?

the wires the hook to the capacitor measure 4 ohms without the capacitor hooked up as you guys predicted.

Is there anything else i can check before I buy a capacitor? Am i right in thinking that if the capacitor is the only thing wrong, then it probably should have started with the pull cord?
Click to expand...

The capacitor is bad, but it should start with a rope.
 
You can try the capacitor replacement, but as I and others have said, if the start winding is the only problem, then manually turning the shaft should start the motor in whatever direction you spin it.

You cannot rule out a burned out winding, shorted turns etc.

Presumably you get some magnetic "hum" noise when power is connected, even though the motor doesn't spin? If not, then maybe the run winding is open circuit?

Have you checked that the power cord correctly supplies power all the way to the terminal block on the motor?

Is there any burnt insulation smell that might be an indicator that it has overheated due to shorted turns?

Hope these clues assist.
 
Before you spend money on the capacitor, take it out of the picture and tie the leads that were on the capacitor together. If the capacitor is bad the motor will start but with a small amount of torque it doesn't need the capacitor to start it only gives it an extra boost.
dwdw47


Tutt said:
i was able to bring the capacitor up to work and measure it. it says 400-440 MFD on the side. we deduced that actually means 400-440 mFD. it measures in the nFD range. The terminals are not dead shorted to each other. So i guess the capacitor is bad?

the wires the hook to the capacitor measure 4 ohms without the capacitor hooked up as you guys predicted.

Is there anything else i can check before I buy a capacitor? Am i right in thinking that if the capacitor is the only thing wrong, then it probably should have started with the pull cord?
Click to expand...
 
Good stuff. I'll try tieing the wires together and take a closer look for burnt windings tomorrow. I've learned a lot so far.
 
dwdw47 said:
Before you spend money on the capacitor, take it out of the picture and tie the leads that were on the capacitor together. If the capacitor is bad the motor will start but with a small amount of torque it doesn't need the capacitor to start it only gives it an extra boost.
dwdw47
Click to expand...

The capacitor is not in the circuit to give it "extra boost". The capacitor is there to change the phase angle between the start and run windings so that starting torque is developed. No capacitor, no starting torque.

Those Howell motors are nice running motors and worth fixing if it's only a bad capacitor, dirty starting contacts and/or bearings. Howell was somehow connected with Kingston-Conley who made motors for Atlas, Walker Turner and others.
 
I didn't get as much garage time as I had hoped today. About all I did was look for signs of a winding getting hot. One winding is a lot darker than the other. What do you guys think?

0517141030a_zps05efd20a.jpg
 
Tutt said:
I didn't get as much garage time as I had hoped today. About all I did was look for signs of a winding getting hot. One winding is a lot darker than the other. What do you guys think?
Click to expand...

The darker color could just be because of a different insulating varnish on the wire. Is there any burning smell?

Does the motor 'hum' when power is connected?

If you measure resistance across the power plug terminals, do you have a very low reading, e.g. 1 or 2 ohms?
 
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No burnt smell, but there is only 1.1 ohms between the power terminals. I measured that without the capacitor hooked up.
 
I did some measuring on MOTOR 2, the 3 phase motor. These seemed more encouraging.

All wires to the chassis were in the Mega ohm range

resistance measurements for delta wiring.
3,5,9 to 1,6,7 - 5.1 ohms
3,5,9 to 2,4,8 - 5.3 ohms
1,6,7 to 2,4,8 - 5.3 ohms

resistance measurements for Y wiring
3,9 to 2,8 - 10.8 ohms
3,9 to 1,7 - 10.5 ohms
2,8 to 1,7 - 10.5 ohms
just for giggles I measures from 4,5,6 to the three legs and they all measured 7 ohms.


i am "pretty sure" I ran it delta when it was pulling too much current. Should I try it Y?
 
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