Instructions schematics I need to see how to thread this machine, what does this have to do with fixing my computer?

Question edited for clarity and spelling 'treading' to threading.
Question moved from Cars and Trucks category to Sewing Machines.

It is a professional machine and in a normal daily working environment needs servicing every 6 months. When was it last done?

https://www.google.com/search?q=kansai+w8103d+threading+instructions

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Domestic Sewing Machine Manuals Instruction and Repair Manuals


Understanding Thread Tension Threads


Sewing Lesson 10 How to Fix Tension on Your Sewing Machine

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Not sure what you mean by "set the bobbin thread." If you need a manual for your machine, search the internet for:

Make + Model + the word "Manual"

The manual should have instructions for winding, installing, and threading the bobbin. There may also be videos on YouTube showing how to operate your machine.

I'm afraid you've threaded your serger incorrectly. I've done it myself more than once, so I try to make sure that I tie new thread to old and pull it through the machine rather than try to re-thread it. That avoids the problem for the future, but doesn't help you now.

Here's what you can do right now to work out the problem:
1. Get out your owner's manual and check the thread path(s) for each thread. Be sure you've got them right, especially the loopers (usually the two threads on the right-hand as you look at the machine).
2. If you don't find any obvious errors, change the sequence of the looper threads - that is, which one is threaded first. I know it doesn't sound like this will help, but it fixed mine.
3. Be sure that none of the threads are caught under the feed dogs, they should pull fairly freely toward the back of the machine.
4. Start sewing without fabric in the machine. I know this is wrong for a standard sewing machine, but you should get a 'chain' with a serger. If it's not 'chaining,' go back and try these steps again.
5. If that doesn't fix the problem, or if it chains and still won't stitch, change your needles. They should be changed now and then anyway.
6. Be sure to lubricate your machine often according to the owner's manual. Most sewing machines need more oil than they get.

Bobbin is not installed correctly.
Bobbin is not spinning in the correct direction when installed.
and the machine does need to be threaded correctly as well.

are you wanting a instruction manual or service manual?

1. make sure your machine is threaded right.2. set the tension between 3 and 4 and play with the tension as you need it to adjust it.3. make sure the bobbin is threaded right.make sure to visit the site below; it has solutions to multiple problems and instructions how to thread the needle or bobbin. Good luck.htt://Fix Looping/Knotting Thread Fix Knotting/Bunching Thread Looping Bunching & Knotting Thread

Good day!

please try this simple tips:

Good day!

A sewing machine operator can often help themselves when their machine does not operate properly.
Here are some simple instructions, which if properly used can save time and mechanics service calls.
TROUBLE;UPPER THREAD KEEPS BREAKING;
This could be trouble;================Do this;
1.Top tension to tight================loosen tension 1 turn
2.Machine improperly threaded=========check threading
3.Thread twisted on guide post========"
4.Thread twisted out of tension======="
5.Take up spring bent or broken=======Check action of spring
6.Thread jumped off pull off finger===Check threading
7.Needle bent or burred===============new needle
8.Bad cone of thread==================try another cone
TROUBLE;LOWER THREAD KEEPS BREAKING;
1.Bobbin tensionspring to tight=======Loosen tension slightly
2.Bobbin threaded wrong===============check threading
3.Bobbin wound to tight or uneven=====try new bobbin
4.lint or thread on bobbin case=======clean inside case
5.Lint or thread inside hook==========clean inside hook
6.Bobbin case nicked bent or burred===check/change case
TROUBLE;MACHINE STARTED SKIPPING STITCHES;
1.Needle bent or burred===============change
2.Needle set in crooked===============Check
3.Thread jumped off take up spring====check threading
4.Thread jumped off pull off finger===check threading
TROUBLE STITCHES SHOWING LOOPS;
1.Forming loops on top of cloth=======Tighten bobbin tension
======================================or loosen top tension.
2.forming loops on bottom of cloth====Tighten top tension
3.Bobbin placed in case incorrectly===remove and replace
4.Bobbin thread slipped from under====check threading of
tension===============================bobbin case
5.Lint or thread in top tension=======clean between tension discs


Thank you and good luck.

you do need to provide more details.  start here - get a fresh spool of high quality all purpose thread such as Coats and Clarks or Metrosene thread, fill a fresh bobbin, install a new size 11 needle.  Follow the threading instructions even if you've threaded the machine a million times, read the instructions again.  try sewing on some basic cotton fabric.  You'll be able to determine if it's the machine.  Breaking thread can be the thread (it does get too old and fragile), the needle, the incorrect needle for the fabric, the wrong thread for the fabric, and a host of other things.  So try that and tell us more if that doesn't work. 

There is a site that has instructions with how to thread the machine properly. Click here for the www.sewusa.com threading section