Somtimes My Clutch Motor Runs Backwards And Sometimes Forwards. Why?

[dikman]

1. If the cap is bulging it's shot.

2. That cct. diagram doesn't indicate a switch or relay, as far as I can see

3. I would think it a little unusual to use a relay in motor like this, seems unnecessarily complicated.

4. If there's no centrifugal switch (the usual way to switch out a start cap) then the cap and start winding are connected all the time. Apparently it's a cheap way to start a motor, as long as it's only a small HP motor. Not the best, imo, but can be done that way.

5. Replace the cap with the same value, stand back and turn it on.

[Art]

If you look where the lines come in, there is a box (could be switch or relay) that has dashed lines for the starting circuit and solid lines for the main (run) circuit. It probably has a cent switch. If it is a Japanese motor, these are a lot quieter than the Taiwanese or Mainland Chinese motors and you would have to listen very carefully to hear it. It could also be stuck in run mode I guess.

Art

[TinkerTailor]

I guess I and most everyone else is saying to themselves that you ain't got the chops to be fooling with this thing. I am not going to tell you what to do, it is over your head. The cap you see is part of the circuit that consists of the start winding in the motor (Aux on schematic) and the start capacitor, and is switched in by the start relay (box with dashed lines), the start relay only switches in the start circuit for a short time then goes to the main windings directly. The following is usually the problem, start relay (box with dashed lines), start winding (not usually), or the start cap. On this model the cap is a 7.5 µF used as a start cap (if the schematic is correct) available at Grainger. This is as much as i can provide for you.

If the start relay is toast (probably) then it will never switch in the start circuit, and just leave the mains switched in and the motor will go whatever way it goes. Sound familiar?

Art

The link is right there in blue.

[TinkerTailor]

If you enjoy denigrating others then indeed you and I are done.

Art is one of many people here who give massive amounts of advice from decades of experience in many fields. He is a huge asset to this site and everyone in this community. He has graciously given you very good advice and the answers to your questions already, as have others, FOR FREE.

He will give advice to anyone with basic knowledge and a willingness to research and learn.

Try to get this much advice out of a motor shop, or a sewing machine shop for free sometime. Specially for a problem that has more than one fix for under 40 dollars........some fixes be under 10 bux..... At professional consulting rates, you probably have 100-200 dollars in advice here from several experts. My local sewing machine guy will not touch a machine for less that 40 bux. Goes up from there.

He is not denigrating, he is stating a fact.

You do not have the skills yet. If you did, you would not ask the questions you have. He is not going to be the one to teach you these skills.

A bit of basic knowledge and 10 minutes googling would have shown you if the cap is rated the same, it will be the same. He looked up the cap in your motor and then looked up a replacement for you, and you still questioned him.

What is wrong with him drawing the line at how much free info he wants to give, and to what level he wants to talk you through it?

There are several solutions to your problem in this thread already. It is up to you to research the parts of those solutions you do not understand, and then choose which one works for you.

[LoveToLearn]

That does not give the right to denigrate others. I wont trade free advice for letting him verbally abuse me for his own self inflation.

Having said that nobody seems to agree if that is a start capacitor, or run capacitor, does it have a start switch or does it not, etc. Is it just the cap or is the whole motor a piece of junk to name a few.. Lots of opinions and I appreciate them all. I have to determine who I should listen to and who not to. It says something about folks when they get their feelings hurt when asked for clarification, so much so that they then need to try to make someone else feel small.

Edited February 26, 2016 by LoveToLearn

[mikesc]

That does not give the right to denigrate others. I wont trade free advice for letting him verbally abuse me for his own self inflation.

Having said that nobody seems to agree if that is a start capacitor, or run capacitor, does it have a start switch or does it not, etc. Is it just the cap or is the whole motor a piece of junk to name a few.. Lots of opinions and I appreciate them all. I have to determine who I should listen to and who not to. It says something about folks when they get their feelings hurt when asked for clarification, so much so that they then need to try to make someone else feel small.

IMHO, insulting a respected moderator and expert, because the advice they give you doesn't come with a special snowflake cherry on top isn't the way to learn ..IIWY..I'd put down the spade and quit digging..

Advice here from the experts is freely given and IME worth it's weight in gold..the humour is a plus..

Take a break, walk the dog, go to the beach, and when calmed down, read the thread again and hopefully you'll see..

[TinkerTailor]

Denigrate is defined as "To criticize unfairly".

As he politely posted earlier, you are in over your head, which is the reason you needed the help in the first place.

He simplified things, and gave you a solution which is workable, and an alternate which will for sure work if the first does not.

He also posted earlier that if the info given here is too complex the job is also. Caps and electricity are dangerous. Amateurs get themselves dead all the time.

You have demonstrated an amateur ability with respect to the diagnosing and fixing of a sewing machine motor through your questions and comments.

He stated this fact. You not being able to look up the part number and values of the cap you have and get a match, specially after he researched it and told it to you was the icing on the cake.

He in no way was unfair in stating that you do not know what you are doing here, and thus was not denigrating you.

He was putting you in your place.

Have a cup of tea, come back tomorrow.

Edited February 26, 2016 by TinkerTailor

[DrmCa]

This is a paper cap, not electrolytic.

@LovetoLearn: Swelling (visible in the last picture) indicates the electrolytic inside the cap is expanding (I.E. failing)

[Art]

This is a paper cap, not electrolytic.

Boy Howdy, if he puts an electrolytic in an AC circuit, pop goes the fuse or breaker. Back in the day, they did have Bi-polar electrolytics, but not here me thinks.

Art

[gottaknow]

I had the good fortune to be apprenticed by two journeyman mechanics. They both had different styles of teaching. The first, a jolly soul who enjoyed life to the fullest. The second (and actually the better of the two), could be a real jerk. I learned a ton from each of them.

I don't know what their problem was, but they both had to take me down a notch on a regular basis. I started training in 1980, by 1985, I was a head mechanic for a contractor with 300 operators, and I was on my way to a very lucrative career.

Sometimes things are laid out for us but that's not good enough. This thread could have been ended after post #2 by Wiz. LoveToLearn, take a step back, realize how much solid advice you've gotten and save your money for a new motor. You'll be glad in the long run. I wasn't paying attention, but by the time you sent me a PM on the 22nd (I advised you get a new motor) you had several folks that I have a lot of respect for, already give you really good advise. I realize now why Art got frustrated. If you truly love to learn, then put yourself in a position to do so. I wouldn't spend a penny on that motor.

Regards, Eric

[dikman]

This has got me intrigued. I'm not convinced that the dotted lines indicate another switch box (or something) - if that were the case I would expect some sort of indication on the drawing. Also, every other cct. that I've seen that switches out the cap/start winding at the very least shows a contact in that part of the cct. whereas this doesn't.

So, I got my spare Consew motor and removed the back cover (where the leads go in). Four wires disappeared into the motor body, a cap was mounted at the back with two wires also heading inside. I looked through the cooling slots, no centrifugal switch. Inside the switch box the four wires were connected as pairs to the line side. I separated the wires and did some testing with a meter. It's wired the same as the earlier diagram, i.e. two wires to one coil (run) and two wires to the start coil via a cap. I started it, but couldn't hear any centrifugal switch, but to be sure I removed the flywheel at the front - no switch.

This one is wired as per the OP's diagram, with the start cct. permanently connected. Not ideal, imo, bit it works and it's obviously cheaper to make.

Lovetolearn, as has been said earlier, replace the cap with the same value. If the motor is running fine, with only the direction being an issue then that's all that's wrong. Without the cap it's simply freewheeling at the start and you have a 50:50 chance which direction it will choose to run.

[Ole South]

@DrmCa

Oil? Liquid? Polypropylene/polyethylene glycol?... is that better? Sorry, I misspoke from too quickly responding, I thought the concept of the wetting agent was more important to the OP. There is a liquid or wax of some form in almost every run/start cap depending on its age/manufacturer. I'm guessing this motor is from the late 60's or 70's so either might be the internal wetter.

[Art]

This has got me intrigued. I'm not convinced that the dotted lines indicate another switch box (or something) - if that were the case I would expect some sort of indication on the drawing. Also, every other cct. that I've seen that switches out the cap/start winding at the very least shows a contact in that part of the cct. whereas this doesn't.

So, I got my spare Consew motor and removed the back cover (where the leads go in). Four wires disappeared into the motor body, a cap was mounted at the back with two wires also heading inside. I looked through the cooling slots, no centrifugal switch. Inside the switch box the four wires were connected as pairs to the line side. I separated the wires and did some testing with a meter. It's wired the same as the earlier diagram, i.e. two wires to one coil (run) and two wires to the start coil via a cap. I started it, but couldn't hear any centrifugal switch, but to be sure I removed the flywheel at the front - no switch.

This one is wired as per the OP's diagram, with the start cct. permanently connected. Not ideal, imo, bit it works and it's obviously cheaper to make.

Lovetolearn, as has been said earlier, replace the cap with the same value. If the motor is running fine, with only the direction being an issue then that's all that's wrong. Without the cap it's simply freewheeling at the start and you have a 50:50 chance which direction it will choose to run.

Of course, the question occurs as to what the dashed lines represent. However, your analysis does bear out with their use of the run cap in the circuit as opposed to a start cap. The run cap having a 100% duty cycle as opposed to a lesser duty cycle for a start cap. Since this application seldom has any startup load and runs at optimum, there is little benefit to a start cap other than getting things spinning in the right direction. If you are going to leave the start circuit "on" all the time, it explains the use of the run cap; as much as this whole design concept can. Why are those damned dashed lines there?

Art

[dikman]

I agree about the dashed lines, Art. That is what's so confusing. Ordinarily, dashed lines like that on a cct., as you said earlier, would indicate that there is something else in cct. and/or that they go via some other equipt (or that it may be a temporary connection). In this particular case that's not happening, so I'm perplexed as to why they used them. I'm blowed if I can think of a (sensible) reason for them.