Victor Electrola Motor Issues

[LimeTree99]

I have a Victor "Electrola" VE-XVI that I acquired last year. I've noticed that after cleaning the motor bearings/commutator, gears, and replacing a few inches of corroded wire, its operating speed seems to fluctuate in a rather predictable "dip" pattern.

Immediately after switching the motor on, it'll start right up to a full 78rpm. It's powerful enough, that even if the turntable is briefly held still, the spindle still spins freely with no rpm loss. This stage lasts about 1-2 minutes, and then it slows down considerably, with the motor barely spinning at around 20rpm. From there, it takes about 3-5 minutes to creep back up to 78rpm, however the motor won't be as strong as it was on the initial start up. At that point, even slightly above average needle friction can slow the motor down.

I've checked the wiring diagram, and it seems to be properly hooked up for normal 120v US house current. I'll admit, I know very little about electric motors, or circuits for that matter, but I would assume that motor bearing or brush wear would cause a consistent speed reduction instead of following a repeatable fluctuation pattern. My only guess is it's something wrong with the resistor coils in back, causing a temporary dip in voltage to the motor.

Does anyone here have enough experience with Victor Electrola models to suggest what the issue may be? Any additional advice would be appreciated.
I'll be able to provide pictures later today if needed.

[barnettrp21122]

I've had quite a bit of experience with a couple of these motors and my guess is that your motor brushes need one or all of these: re-seating, replacement or tension adjusted as it contacts the commutator. The commutator itself can be smoothed using a finishing stone. Your goal is to provide maximum contact and steady pressure between the brush surfaces and commutator.

If you can pm me with a couple pictures I'll go into further detail.
Bob

[JerryVan]

I would start by attaching a voltmeter to the resistor pack terminals that lead to the motor. You should see 32 Volts there. Run the motor until it begins to slow and notice if the voltage has dropped at that time. If you don't have a voltmeter, you can get one really cheap, or free sometimes, at Harbor Freight. Also get some test leads with alligator clips at each end so you can hook up the voltmeter without having to constantly hold to test probes in place. So, first step, see what voltage is getting to the motor...


If you let things sit for while does it return to full speed & power?

My only guess is it's something wrong with the resistor coils in back, causing a temporary dip in voltage to the motor.

That's what I'm thinking also. The resistor coils will get hot after running for a bit. With the heat will come expansion. The expansion/movement may be putting pressure on a lose electrical connection, causing a poor connection and a voltage drop. Try unplugging the phonograph, then going through each connection, making sure it's tight. Might also help to run it in a dark room while looking at the resistor pack for any signs of arcing.

[LimeTree99]

I've had quite a bit of experience with a couple of these motors and my guess is that your motor brushes need one or all of these: re-seating, replacement or tension adjusted as it contacts the commutator. The commutator itself can be smoothed using a finishing stone. Your goal is to provide maximum contact and steady pressure between the brush surfaces and commutator.

If you can pm me with a couple pictures I'll go into further detail.
Bob

You were right! It was the brush tension (and probably grease.) Voltage was consistent when I measured for 10 minutes using a multimeter, so the resistor coils weren't the issue.

The issue was, the spring loaded arm that "clamps down" on one of the carbon brush blocks wasn't producing enough pressure. Someone doing motor repair must've lost the original spring for it, and made a crude one themselves. I had to fiddle with that junk wire until I got even pressure on both sides, what a pain that was. Both brushes were removed and wiped clean before reassembling.

Just played three 12" records in a row without any signs of slowing down. Normally it wouldn't have been able to get through a single 10" record.

Thank you for leading me in the right direction.

[JerryVan]

Great news! Thanks very much for the update

[LimeTree99]

Must’ve spoken too soon. The motor might’ve been only half of the issue.
Voltage across the resistor measured once the motor slowed down:
85.8V - 86.5V

Voltage across the resistor after giving it approx. 10 minutes to speed up:
83.5V - 84.0V

This is much higher than the 32 volts I supposedly should have. Perhaps the motor is getting overloaded? Seems odd that the motor got stronger as the voltage decreased by a few volts. I’ve attached photos of the wire setup.

Edit: Steady 37.3V - 37.9V measured at the point where the 2 wires plug in to the motor.

[ChuckA]

Must’ve spoken too soon. The motor might’ve been only half of the issue.
Voltage across the resistor measured once the motor slowed down:
85.8V - 86.5V
Voltage across the resistor after giving it approx. 10 minutes to speed up:
83.5V - 84.0V
This is much higher than the 32 volts I supposedly should have. Perhaps the motor is getting overloaded? Seems odd that the motor got stronger as the voltage decreased by a few volts. I’ve attached photos of the wire setup.
Edit: Steady 37.3V - 37.9V measured at the point where the 2 wires plug in to the motor.

The motor will run between 35 and 42 volts, the resistors drop the incoming AC mains voltage to that range. If you have AC mains 120VAC then the voltage drop across the
resistors will be about 78 - 85 VAC. The actual voltage drop will depend on the actual resistance of the resistor and the actual current the motor is drawing.

With the motor running and you measure 35 to 42 volts on the motor terminals you're OK.
If the motor takes 10 minutes to speed up you have other problems. 10 seconds would be too long.

Chuck

[bkasindorf]

What we did was get a variac and bypass the resistor pack and run 32 to 40VAC right to the motor and see how it behaves. Get a current meter variac so you can look at the load.
The brushes wear in for the first hour or so of running with new ones so things change. See if the current is constant. If not the governor may have issues or bad grease on the moror bearings.

[JerryVan]

What we did was get a variac and bypass the resistor pack and run 32 to 40VAC right to the motor and see how it behaves. Get a current meter variac so you can look at the load.
The brushes wear in for the first hour or so of running with new ones so things change. See if the current is constant. If not the governor may have issues or bad grease on the moror bearings.

I used to run my VE-XVIII with a Variac until I located a resistor unit. They work great.

Not sure if it's already been mentioned, but these motors tend to collect oil on the commutator & brushes. The oil mixes with carbon dust from the brushes and creates a semi-conductive goo that leads to poor commutation. Be sure the commutator and brushes are cleaned of any oil or the black sludge that it creates. Also, be sure that the brushes can slide freely in the brush holders. Any resistance to slide freely will affect brush contact with the commutator and therefore motor performance.

When the motor runs, do you notice any arcing or sparks between the brushes and commutator? A tiny bit is acceptable. Anything more than that indicates an issue.

[LimeTree99]

What we did was get a variac and bypass the resistor pack and run 32 to 40VAC right to the motor and see how it behaves. Get a current meter variac so you can look at the load.
The brushes wear in for the first hour or so of running with new ones so things change. See if the current is constant. If not the governor may have issues or bad grease on the moror bearings.

I used to run my VE-XVIII with a Variac until I located a resistor unit. They work great.

Not sure if it's already been mentioned, but these motors tend to collect oil on the commutator & brushes. The oil mixes with carbon dust from the brushes and creates a semi-conductive goo that leads to poor commutation. Be sure the commutator and brushes are cleaned of any oil or the black sludge that it creates. Also, be sure that the brushes can slide freely in the brush holders. Any resistance to slide freely will affect brush contact with the commutator and therefore motor performance.

When the motor runs, do you notice any arcing or sparks between the brushes and commutator? A tiny bit is acceptable. Anything more than that indicates an issue.

I did notice a bit of black "sludge" on the commutator after cleaning, and it re-appears even after a thorough wipe-down. Both brushes slide smoothly in their slots, but the inside of the motor looks rather blackened and dirty after inspecting it with a flashlight, so I'm wondering if old oil/grease has broken down any fragile internal components, such as insulation or just the windings in general.

I've decided I'm just going to take the motor to a local repair shop and get it re-wound. If anything is seriously wrong with it, a professional would know what to look for.