Tornado Pinion K50334590

The pinion (part# K50334590) is the genuine Tacony small gear in the brush-head height adjustment. It is the piece that turns dial movement into actual travel at the wheel, and because it is small, cheap and plastic it is usually the thing that has failed when a height setting will not hold.

This is a genuine Tacony OEM part. It appears on the 19-inch brush head sheet. Tacony lists it without a callout number on that sheet, so it has a row in the parts table and no numbered dot on the diagram.

Compatible Models for the Pinion K50334590

• Tornado CV 38/2 (91415) — 15-inch dual motor HEPA
• Tornado CV 48/2 (91419) — 19-inch dual motor HEPA
• Tornado CVD 48/2 (91442) — 19-inch dual motor HEPA

Tacony lists this pinion against three machines. Note that it is on the 19-inch sheet but also fits the 15-inch CV 38/2, so do not assume from the sheet alone that it is 19-inch only.

What the pinion does

The pinion meshes with the adjusting mechanism so that turning the height dial raises or lowers the brush head in defined steps. When its teeth are worn or stripped, the dial turns freely and the head settles wherever gravity and the carpet put it — which is why brush height stops holding between passes.

Signs it needs replacing

A height dial that spins without resistance or without changing anything, a setting that will not stay put, or a gritty feel as the dial passes one particular point. At this price it is worth replacing on suspicion rather than diagnosing at length.

Installation and fit

Bench job with the head opened up. The pinion sits in the adjustment assembly behind the top cover; check the adjusting wheel K45153160 at the same time, since a stripped pinion is often the symptom of a seized wheel rather than the cause.

Frequently Asked Questions

My height dial spins freely — is this the part?

Very likely. A stripped pinion is the usual cause of a dial that turns without moving the head. Check the adjusting wheel as well; if the wheel has seized, a new pinion will strip too.

Why does it appear on the 19-inch sheet but fit a 15-inch machine?

Tacony catalogues parts by where they are drawn, not by every machine they fit. Where-Used lists this pinion against the CV 38/2 as well, which is a 15-inch machine.

Is it sold singly?

Yes, one pinion.

Do I need to replace anything with it?

Not necessarily, but inspect the adjusting wheel while the head is open. Replacing a stripped gear without freeing whatever stripped it is a short-lived repair.