J Miller

Does your 328 or similar Singer clatter ..........
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............. like Danica Patrick's race car just before the engine blew?

Well here's a tip, check the gap between the heal of the bobbin case and the cushion spring on the bobbin case latch using a narrow gap gauge. Red arrow in the second pic.
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The gap should be between .010" to .015" on a 328, but find the specs in the service manuals for other models. This one was set at .032" and the machine sounded like it was gonna throw a rod.
You adjust it by loosening the closest screw to you on the right of the bobbin case.

Once the gap was reduced to .013" the clattering stopped and the machine actually sounded like a sewing machine.
Sewed better too. The tension is affected by this gap if it's too tight or too loose.

Joe