Jointer motor

[John T Barker]

My jointer is pretty old (about as old as me-50+, maybe more) and the motor has got issues. I described the problem, pretty sure I knew the answer to an electrician and she confirmed that the capacitor had gone bad. It hmm'ed when I pushed the button and would eventually get going if I grabbed the belt and gave it some help. The electrician advised me to remove the capacitor (with caution) but there is no external capacitor. No bulge on the side of the motor. Can I still remove it? Can it still be replaced? I'd hate to have to buy a new motor when this one functions...with help.

[Judson Green]

I have a small craftsman motor that has the capacitor in the base of the motor.

[Larry Copas]

Repulsion induction motors didn't have a capacitor. You might have one of those since you said the machine was 50+ years old. A picture or description would help.

And yes it could be hid away in the base or somewhere else but not all that likely.

[Jonathan Freinkel]

Check these out - http://www.appliancecarestore.net/supco-spp6-solid-state-relay-hard-start-booster-ac-capacito6.html

ive used them when the capacitor was integral and worked well.

[Jim Andrew]

Harbor Freight has some reasonably priced compressor motors, saw they had the 3 hp on sale last week.

[John McClanahan]

I have seen a few capacitor start motors that have the capacitor inside the motor, near the rear bearing. If your motor is rather large for its HP size, the capacitor may be inside of it.

John

[Ole Anderson]

I have an old 6" King Seeley (Sears) about that vintage. It actually came without a motor. I started with a discarded 1/2 horse motor that served me for years, but when it started doing what yours is doing, I swapped in new Dayton 1 hp TEFC from Grainger. My son worked there at the time so I got the employee discount.

[Rod Sheridan]

John, the motor may not be a capacitor start motor.

It could be a repulsion-induction motor (not that likely if the motor is from the sixties) or it could be a split phase motor.

The split phase motor is similar to the capacitor start, both use a run winding and a start winding that is disconnected when the motor reaches aproximately 75% of rated speed. The capacitor start motor has a capacitor in series with the run winding to increase starting torque.

An open capacitor or starting switch will produce the same effect, no rotating field so no rotation.

Regards, Rod.

[John T Barker]

Did I mention that when it comes to electricity my knowledge beyond plugging it in is the belief that demons go up and down the wires to make the motor run? Appreciate all the suggestions and comments. I will take a picture of the entire motor and plate tonight and post it. I'm looking to save myself any undo expense right now but certainly will replace the motor if absolutely necessary. My area has Grainger, Harbor Freight and a multutude of motor places so I should be able to find something when I go that route.
Thanks.

[John T Barker]

Check these out - http://www.appliancecarestore.net/supco-spp6-solid-state-relay-hard-start-booster-ac-capacito6.html

ive used them when the capacitor was integral and worked well.

Thanks. Is that a replacement to the internal capacitor? I'm not very electrosavy.

[Judson Green]

Grainger should have some, amazon too. Once you figure out if you have one, there should be some numbers/code on it, from there it's usually easy to figure it out. Unless you've got a special size, then things might be difficult.

[Joe Kaufman]

40-50 years ago simple split phase motors were commonly usedin low inertia starting applications. They did not use a capacitor but relied on the different inductive reactanceof the starting and running windings to create a phase shift differential inthe current flow providing starting torque. The reactive difference was created with wire gage size and number ofturns in the coils. The addition of a capacitor in series with the startingwinding increased the phase shift between the windings and therefore increased startingtorque.
Both types require a method to disconnect the startingwinding once the motor is rotating, usually a centrifugal switch. Some motors – not common - were equipped witha relay imbedded in the starting winding to disconnect the startingwinding. This type is effectively a nonrepairable motor if the relay fails.
The most common problems are the contacts of the centrifugalswitch are not closing – burnt contact surfaces or open starting windings –someone already released the manufacturer’s prepackaged smoke from of the motor.

[Jeff Deutsch]

My bet is that the contacts on the centrifugal switch are shot but but tech advice of this type is not going to help John if he is not familiar with electrical work. Rebuilding a motor by yourself with no training is not a good idea. A replacement motor is probably the best bet. I have an old 4 3/8 King Seely Craftsman jointer that had a craftsman motor that died. I threw it into the "for future research" pile and threw in better one that came out of my band saw when I up graded to a bigger motor. This discussion has aroused my curiosity; I may go pull the old Sears apart to see how it is wired. Somebody said that the start and run windings are in series. The drawings I have seen always show the run winding connected to A.C. power. The start winding in series with the start capacitor and the centrifugal switch are wired in parallel with the run winding. When the switch opens only the run winding is connected. By the way there is a product on the market that is an external, solid state replacement for a centifugal switch.It is just a little box that you mount on or next the motor so its wires can get to the old switch connections between the cap and the line. They are available in 120V and 220V. You match the switch to the current rating, as shown on the info. plate, of the motor. Sorry I have forgotten the company name. They work great. A life saver if you can't find a new switch and a nicer way to go even if you can. I don't recall it being that expensive. A motor at work had one as original equipment.

[M Toupin]

Geez, 12 posts and all pure speculation...

How about we wait for the OP to post pics and get an idea of exactly what he has, it might be as simple as a new capacitor for $5. Recommending a replacement motor purely on speculation is a bit over the top don't ya think?

John - post some pics of the motor and the name plate and maybe we can give you a bit more informed recommendation. It might be a good idea to pull the motor out and look underneath too, some motors have the capacitor in the base as mentioned already. If it is the capacitor then it's only 2 wires, not difficult or dangerous at all and a heck of a lot cheaper than a new motor.

Mike

[Jeff Deutsch]

Geez, 12 posts and all pure speculation...

How about we wait for the OP to post pics and get an idea of exactly what he has, it might be as simple as a new capacitor for $5. Recommending a replacement motor purely on speculation is a bit over the top don't ya think?

John - post some pics of the motor and the name plate and maybe we can give you a bit more informed recommendation. It might be a good idea to pull the motor out and look underneath too, some motors have the capacitor in the base as mentioned already. If it is the capacitor then it's only 2 wires, not difficult or dangerous at all and a heck of a lot cheaper than a new motor.

Mike
I wrote the post just above yours. As I said, My old Craftsman jointer had a Craftsman motor that is about the same vintage as John's. I just took a look at it and it says, in big print on the outside of the motor: "1/3 HP Craftsman SPLIT PHASE motor. In motor terminology that means that there is a main winding and a start winding that is in parallel with the main winding until disconnected by the centrifugal switch. There is no capacitor in a split phase motor. Like I said, it is probably the switch, whether it is cap start or split phase . Centrifugal switches are motor specific, not like a capacitor. Finding a replacement for an ancient switch would be difficult for someone that knows their way around. Maybe the contacts could be cleaned. I have been in electronics and electromechanics for many, may years. If you read John's post. He honestly states he has no knowledge what so ever. Over the years I have repaired things for people. Take him at his word when he says I doesn't know what he is looking at. You were right about one thing. Info on the motor would be helpful. Probably no picture needed if motor is clearly labeled like mine. Split motors have poor starting torque, even with a start winding but can be used in devices that do not start under load, like a jointer. John's post is not current so he probably resolved his problem already.