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Hey Ed,
Where is your sense of adventure!

The contact plate and centrifugal switch is only about $11 to replace on the Grizzly motor and I would almost bet yours would be the same.

Ed, you do want to drain the capacitor before touching it. They can hold energy for a while.
Good luck.

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Jim Watts
http://jameswattsguitars.com

Right! Drain the flux capacitor before attempting the gravitron switch!

It won’t be 1.21 gigawatts, but it could be enough juice to make you regret not draining.

I haven't read all of the earlier responses. but, have you checked the switch, I've had several of those go kaputz on me over the years. Done that? then, carry on:)

I'd look for a video on draining capacitors safely, then replace the start capacitor. If the capacitor isn't bulging, it probably isn't the issue, but at least it's an inexpensive test.

If not, it's your motor. When the motor in my bandsaw went bad, it gave an electrical hum but wouldn't turn. I found a replacement Leeson farm duty on Amazon for next to nothing compared to retail.

Hmm...

I'll start with the capacitor, then the centrifugal switch...

Draining the capacitor seems to happen naturally by letting it sit, or simply arcing it by touching both poles simultaneously with an insulated handheld object. I hope I don't need to replace the motor...

The charge on the capacitor can be measured with a multimeter, a tool which is likely to be in most shops doing any electrical repair work, or should be. Compact auto-ranging multimeters can be found for under $25, and good, basic select-range digital meters with most necessary functions for under $10.

To check for the state of the capacitor's charge, set the meter to the highest DC voltage range (or auto-range on auto-ranging meters) and attach the test leads to the + and - leads of the capacitor. Measured voltage should be 10 volts or less; anything higher and the capacitor needs to be discharged.

To safely discharge a capacitor, use a 2 watt or larger 1K to 10K range resistor and a set of insulated test leads across the terminals of the capacitor, then recheck voltage. Use a search engine and look for 'Discharging Capacitor Amplifier' for video and test articles on making and using a bleed resistor - we use Duck Duck Go, which is an ethically operated search engine that does not seek to skew search results, track our queries, or sell that data.

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For the times they are a changin'

- Bob Dylan

I think a multi meter is on the list for sure, especially since the elements on the range top have all stopped working. I don’t mind cooking outside on the bbq but I sense the lady would prefer it were fixed before winter...

It's funny how wives don't feel a hot plate, an electric frying pan, and a crock pot is an adequate replacement for a range top. They treat them as alternative facts.
The last time I worked on a range I "fixed it" to the point buying a new one was cheaper than continuing to fix the old one (I cracked the smooth top).

Again I hmmm...

Really hoping some cheap Lowe’s components and a multimeter will get things sorted. After a few days trout fishing of course...

Sounds like you have your priorities straight.

Right, so I got a multimeter and today tried to test the capacitor. It looks good, no leaks or bulges or anything visible.

I set the meter to 2000 ohms. Online instructions say that the reading should steadily have gone up to max reading, but instead it went through a bunch of random numbers then went to zero. Didn’t seem to matter which pole I put on red or black...

Any thoughts?


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An ohm meter puts out a voltage for testing then reads the result across the resistor on an ammeter per the formula volts=ohms x amps, a good cap will slowly charge until it is at max volts which will read max ohms on your multimeter. Looks like your cap is probably bad or at least leaky.

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Steve Smith
"Music is what feelings sound like"

Well that’s good news then as it’s easily replaced (I think)

Well that's interesting. When the capacitor is detached to the machine, the readout streadily goes up to read about 1650 then hovers there. When re attached to the machine, I get a read of 300 dropping to zero...

That's because your measuring the motor windings when it's attached.

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Hutch

Get the heck off the couch and go build a guitar!!!!

Ah I see. So doing it attached to the machine is no good then.

Steves post above makes me think that perhaps the cap is good then, as when tested off the machine the ohms steadily climb?

Gotta be detached.

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Steve Smith
"Music is what feelings sound like"

Am I right in thinking that it's probably good as there are no bulges and leaks, and when detached, the ohms steadily climb on the tester?

if you are on the 2000 ohm scale and the ohms climb up to the max scale reading then the cap is probably good.

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Steve Smith
"Music is what feelings sound like"

It went to about 1650, do you think that's still ok?

If you can repeat the test several times (short out the cap between tests) and get the same result then the capacitor is likely ok. On the other hand, if you are trying to get the motor cleaned up to run for the next xx years you could just replace it, they're not expensive.

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Steve Smith
"Music is what feelings sound like"

I'm going to get a new one and see if that helps. I can always return it. It's about the only thing I feel qualified to do. I took off the fan cover and the bottom of the motor is sealed quite well, looks like a job to get into the centrifugal switch. I'm not convinced it's the switch any way, as I can get the motor to speed by handrolling the drum, and you can clearly hear the switch click in and out which makes me think it's working but I don't know.

I'll get a capacitor and see what happens...

I had a switch that would function like that sometimes.
It appeared that dust had built up in the switch, caused some arcing at the contacts, and over time caused enough of a voltage drop that the motor would only hum. I could get it go by helping, but would not run at full power. Of course the switch in question was actually able to be opened. I cleaned it out and ran a points file over the contacts and it all worked fine.

B

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My memory is so good, sometimes I remember things that never happened.