bkay

I'm working on T&S to get them ready for the quilting kids. The 778 still sounds like a thrashing machine, but it is sewing ok. I started on the 756 which is the same machine except it's not a portable.

I was using this machine last year for piecing. It slowly almost died. It started to hesitate and then the handwheel got hard to turn. I worked on it and posted on it and worked on it some more. At the time, Terry of Tandtrepair.com said it was the cracked cam stack that made it hard to turn. It doesn't exactly have a cam stack. It has no built in cams, just the removeable ones. I finally got it working and moving by just oiling the "fool" out of it. It's been in the back building since then. Now it's back to the same old problem.

Joe M. has posted that a cracked cam stack does not make the machine inoperable. The plastic under the place you put the cam could either be cracked or a two piece collar. The gears I can see all look fine. I did some more clean and oil. I'm better at that since I worked on that 401 with the stuck cam stack, but it doesn't seem to help.

What it actually does is bind at the highest point of the thread take up lever. When you get past that point in the rotation, it loosens up.

Any ideas of what I should be looking for?

bkay

quiltedsunshine

Just a thought... When the thread take up is in it's highest point, the feed dogs are too. So, is it still binding if you remove the presser foot? I've caught myself trying to figure out why it binds at that particular point, and a lot of times, it's the feed dogs, just doing what they do, and creating pressure on the presser foot.

bkay

The presser foot is removed and so are the feed dogs and bobbin case. It doesn't change anything.

I'm beginning to question if it's something in the bobbin area. I've cleaned it and oiled it and it did not make a difference. I wonder if it might be the stuff under the bobbin area.

While waiting on inspiration and information, I've begun to work on the 750 Leon sent me. The camstack is not cracked.

Also, someone believed in greasing plastic gears, that's for sure. Whether you think you should grease plastic gears or not, these gears are still there. The one under the bobbin area has one tooth missing.

It inspires me to be more generous with my grease.

bkay

cjr

I sew on a 778 regularly. Mine is a work horse. I LOVE It. It needs lots of oil , especially in bobbin area. Oil attracts lint. I clean mine with every bobbin change with a pipe cleaner. Also be sure to cut any thread from starting to wind off. That can cause noise and not work. I have not had it commercially serviced in 5 years. Any little bit of lint or 1/8 inch of thread caught somewhere will cause improper stitching. The only 2 replacements have been the feed dogs, original rubber to metal and foot pedal. Also regularly changing needles helps. I use that machine for an average of 5 hrs daily.