My 28 year old Crown Point Sewing machine is just starting to revolt. Type SANWA - SZA-645 FL / CI;
I have looked after it, oiled and cleaned it + using the vacuum to get out loose threads and dust!
I pulled it out yesterday to stitch up a cover for the dog bed and needed to refill a bobbin. Loosening the inner wheel on the big wheel as required, and loading everything up, it just kept spinning but no 'drive' on the bobbin! I adjusted the pressure wheel that sits against the bobbin wheel; eventually I got the bobbin refilledd after fiddling - it picked up when the bobbin was almost half full and then completed to fill ok;
I took the inner handle/wheel off checked it, checking the plate/clutch was back on correctly - still no good. Sounds like the drive belt just spins and it won't fully drive the needle through the thinnest of material. The motor sounds fine.
I can feel the belt is still attached with a screwdriver with some stretch/play on it; I got the job done, but 5 times longer than it should have.

Marianne Cottee, May 2008

Hello Marianne,
If it is a rubber belt the chances are it may have stretched and lost it's ilasticity, either that or the screw has come loose on the pulley wheel of the motor, is the motor internal ? quite easy to change the belt which it probably needs by now, any problems e-mail me.
Ken

drivewithken@blueyonder.co.uk, May 2008