Tornado Tempest Microswitch Screw M4 x 16 K73032050

The Tornado Tempest microswitch screw (part# K73032050) is the M4 x 16 machine screw that fastens the power microswitch (part# K66303310) and its housing (part# K50609980) to the electronics plate of the TV400-W26-U cordless wide-area sweeper. Tacony lists it as Screw 4×16, Microswitch, Tempest — the machine uses several M4 fasteners, and this is the one specified for the switch mounting.

Getting the right screw here matters more than it does elsewhere on the machine. The microswitch has to sit at a fixed distance from its actuator, and the screw length is part of what sets that. A screw that is too long bottoms out before the housing is clamped, leaving the switch able to shift under load; one that is too short does not engage enough thread to hold against vibration. Either produces the same result — an intermittent start that looks like an electrical fault.

Compatible Models for the Microswitch Screw M4 x 16

• Tornado Tempest Wide-Area Cordless Carpet Vacuum Sweeper — Model TV400-W26-U

When to replace it

• The thread is stripped, crossed or galled from a previous repair.
• The head is rounded or the drive recess is chewed out.
• The screw has backed out and been lost during a strip-down.
• Corrosion has seized the screw in its boss.
• A non-standard fastener was substituted at some point and the switch will not clamp square.

This is an inexpensive item that is worth replacing on sight rather than reusing a marginal one. If you are fitting a new microswitch or housing, order a fresh screw with it — the cost is negligible next to a second strip-down caused by a fastener that would not hold.

Fitting notes

The screw is used with a spring washer and hex nut. Remove the battery pack before working in the control area. Tighten it enough to clamp the housing solidly without distorting the plastic — over-torquing an M4 into a moulded boss is the quickest way to crack the housing you have just fitted. After tightening, operate the control through its full travel and confirm the switch still clicks at the correct point.

Twin City Vacuum has been selling and servicing Tornado equipment since 1956. Browse the full Tornado Tempest parts range, or see the Tornado Tempest TV400-W26-U machine. Manufacturer information is at tornadovac.com.

Frequently Asked Questions

What does the microswitch screw do on the Tornado Tempest?

It clamps the power microswitch and its housing to the electronics plate, holding the switch at the fixed distance from its actuator that lets the circuit make and break at the correct point of travel.

How do I know if my microswitch screw needs replacing?

Replace it if the thread is stripped or crossed, the drive recess is damaged, the screw is corroded into its boss, or it has been lost. If a previous repair substituted a non-standard fastener and the switch will not clamp square, that is also a reason to fit the correct part.

What models is the microswitch screw (part# K73032050) compatible with?

The Tornado Tempest TV400-W26-U wide-area cordless carpet sweeper. Tacony specifies this M4 x 16 screw for the Tempest microswitch mounting.

Can I use any M4 x 16 screw instead?

We would not recommend it. The length and head form are what set the switch position and clamp the moulded housing without splitting it. Given the price of the correct part, substituting is a false economy.

How do I order the microswitch screw (part# K73032050) or get help?

You can add the microswitch screw (part# K73032050) directly to your cart on this page, or call us at 763-535-0770. Our staff at 5415 West Broadway, Crystal, MN 55428 has been servicing Tornado equipment since 1956 and can help confirm the right part for your machine.

Questions? Call us at 763-535-0770 or visit us at 5415 West Broadway, Crystal, MN 55428.