These are very good machines and well worth spending some time and money on. We often underestimate them because they are old, can be found at bargain prices, and not really worth much more if we sell them. The investment of handing it in for a service or a thorough DIY cleaning and oiling will pay off with these models. There aren't that much better machines made today. Technology has moved on and nice new models with fancy functions, step motors, advanced computerised soft- and hardware, but very little out there will replace a solid basic sewing machine like this.
Take care of your 403a it's worth keeping it up :- ) It's only when we are on our fourth and fifth vintage machines we don't want to pay much at all for it, because we often only make use of two or three of thems. I make a point of keeping a regular cleaning and oiling routing on my machines. Once a year or so I go through all the parts from top to botton more thorough clean up and polish up parts if needed. As we get to know the machine better, read up on info available we get to sort out the major or minor issues a long the way.
Last edited by Mickey2; 07-30-2017 at 05:13 AM.