Hello Marc,
First of all there are no grease points on the SNK motor on the 400 series, if the motor is running slow then it means a new motor, if you want to take the motor out to clean it and see this is what you need to do, take the bottom off the machine, take the end off the machine, look at the big holes drilled in the end of the machine where the motor is, the motor is suspended by two nylon pins, slacken off the big tension screw so the belt goes slack and slacken of the pins as well, move the pins down if you have to so you can get the motor out, you may need to undo the plug on the end of the machine as well.
Ken
ken
January 2011