Saturday, October 4, 2014

Random Decision

 After breakfast I pulled myself away from the computer and headed out to either the sewing loft or the shop. Admittedly I was reluctant to tackle the Necchi.  I had not checked in with the Yahoo Necchi Group (which turned out to be a poor decision).  I really wanted to sew but that dang Necchi was calling to me.   I went to the shop first, thinking that if the door is unlocked I will work on the Necchi, if not, I will sew. 

 It was unlocked.  My fate was sealed.

The electrical problems plaguing this machine have been haunting me.  I did solve one of the  problems.   I bought a new cord and the machine ran well, the light worked appropriately, but the motor smoked.  That was worry number one.  

I took a good look at the electrical on the underside of the machine.  It looked complicated and threatening.  I wondered how I would get at it.
 I took another look at the motor itself.  I decided that those bolts looked less threatening. 
So I loosened the ones attached to the motor and released the belt.

 Then I felt a presence behind me. It was almost as if he were saying "Do you really think you should do that?"  
I ignored him.  I think he was waiting for a treat.

I took another look under the machine.  This time I located the motor leads and where they connect to the electrical terminal.  I labeled the top one.  You can't see it but I wrote TOP on that yellow tape.  I need to be very explicit when I am venturing into new territory. 
I removed the plastic protection device.

I then loosened the screws holding the motor leads in place and released the motor leads.  
Then I removed the motor mount bolts and  VERY CAREFULLY removed the motor.
The rubber grommets in the motor housing and the machine bed were shot.  They were melted from over exposure to oil.
The brushes and commutator were easily accessible.
The brushes were saturated with oil.
I soaked them in denatured alcohol for a while and then burned the oil off using a lighter.  When there was no more flame, I declared them done.

All clean and shiny
Just as carefully as I took the motor out, I placed the motor back inside the machine.  As I turned the machine over, a washer fell out.    I wondered where it belonged. Then I figured it out (see the photo above) .  I found the other inside the machine.  Lucky me.
It didn't take me long to figure out that I had to remove the mounting bracket from the machine bed in order to get the motor and these washers back together the right way.  That's because my brain was working.
The bolt into the machine was pretty oily

and there was a little puddle of oil between the machine and the mount.  I got a bit concerned that maybe the oil had filtered into the terminal.  So, I took another look at that and decided that I would see if I could get it off the machine.  

There were only three screws that held it in place .  I did have to remove the lamp connection, but that was easy peasy.  I don't have a photo for that .
I was pretty relieved to see that it wasn't oily or compromised at all.  I was able to slip it back together.

Problem number 2: the power cord that came with the machine is wired incorrectly.   When I use it   the light comes on but dims when I apply the foot controller and the motor doesn't run at all.  If I switch the cord around in the wall plug, the machine runs slowly and the light dims and the light doesn't turn off.   There is no change in power from min to max.  Something is wacko.   The machine runs fine with the after market replacement cord but the insulation on the wires prevents a good fit.  The cord will wear out in no time.

In fact, in an effort to figure out how the cord should be wired, I took apart the new cord and discovered that it was already wearing out.  In my effort to understand the wiring, it broke.
A and B are actually two different wires.  I point this out because they look like the same wire in this photo.

The next few hours were spent in a futile effort to get the power cord re-wired.   Oh how I wish I had checked the Necchi group first, as I had planned.   Finally, I did . There I found clear instructions with a photo and in less than thirty minutes I had the sucker re-wired.   The motor doesn't smoke, the machine runs in Min or Max and the light doesn't dim when I apply the foot controller.  In other words.  I FIXED IT!!

10 comments:

  1. Woo-hoo! You are one brave soul who tackles smoking electrical motors. I am so grateful for those who take time to post useful and invaluable info to fix these beauties. I was able to put the tension back on the White someone asked me to fix because of a posted diagram. Sadly, if I had also read the forum first, I would have never taken the tension apart in the first place.

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  2. I've been too afraid to touch any motor yet. Glad you got this one fixed. I really should pull out my Necchi Supernova and see if it even works.

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    1. Yes, you should pull it out. So far this one is a smooth runner. I can't wait to get it stitching.

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  3. I thought your post was interesting - but - I just love your Dog! - how can you ignore him (her?). So cute - what breed is it?

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    1. Wilson is not so easy to ignore. I have learned over the past ten years how to do so. He gives up, eventually, and lies down. Wrigley, is brother, is more inclined to settle right under foot. He is much more difficult to ignore and move, I might add.

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  4. Good on you. I'm going to be tackling my first motor re-furb so these posts are very helpful.

    Btw, how is Wilson? Some weeks ago you wrote that he wasn't feeling well. I would have a lot of trouble ignoring a dog with soul and Poodles are soulful creatures.

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    1. Wilson is much better. Thanks for asking. I have supplemented his food with powdered glucosamine with MSM (Nupro) and he is no longer lame. The other two dogs get it too. They all seem to be more limber and more frisky

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  5. Gosh you have taken the fear of lusting for a vintage machine that is "not quite right". This is my first time here and glad I found ya, if it keeps raining I may red the whole blog again thank you.

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  6. Gosh you have taken the fear of lusting for a vintage machine that is "not quite right". This is my first time here and glad I found ya, if it keeps raining I may red the whole blog again thank you.

    ReplyDelete