Eureka Ultra Upright Switch...
$6.99
Product details
If a Eureka or Sanitaire SC684 series upright has started needing a firm push on the power rocker before it catches, part 137385 is the replacement switch built for that platform. This same switch carries over across a broad set of Ultra and commercial upright models sharing the SC684 chassis.
Switches wear from the inside out. The contacts pit and build up carbon over thousands of cycles, and the failure shows up first as inconsistent starts, then as a machine that cuts power if the cord or body gets bumped, and eventually as one that will not stay on at all. None of those symptoms point to the motor or the cord, which is why a bad switch often gets misdiagnosed as something more expensive.
- Part: 137385 switch
- Fits: Eureka and Sanitaire S635A, S645A, SC684F, SC688, SC689A, SL635A, SL635B, NT1199D1
- Function: Rocker switch controlling power at the handle
- Tell: Inconsistent starts or power that cuts when the machine is bumped
The replacement drops into the same cutout and reuses the existing wiring leads, so no splicing is required. Disconnect the machine from power first, and check your rating plate against the models above since the SC684 platform covers several closely related variants.
Because this switch is listed across such a wide range of SC684-based machines, keep the old switch once it comes out rather than tossing it straight away. Having the worn unit on the bench to compare against is the fastest way to confirm the right part when a second machine in the fleet develops the same starting symptoms.

