Tornado Nut Hex Jam 3/4-18 Slotted Zinc Plated 30261

Three things in this specification matter and each one is a way to order the wrong part: it is 3/4-18 (a fine thread in a large size), it is a jam nut (thin), and it is slotted. Part number 30261 is the genuine OEM nut, zinc plated. This is the 230-volt part, fitted to the Tornado 98167 20″ Marathon 800 carpet extractor (8 Gallon, 230V).

Compatible Models for the Nut Hex Jam 3/4-18 Slotted Zinc Plated

This part is shared across a wide run of machines. On the Marathon 1200 family it is fitted to:

• Tornado 98168 12 Gallon Self Contained Carpet Extractor
• Tornado 98168 20″ Marathon 1200 Carpet Extractor (12 Gallon, 115V) — all series
• Tornado 98169 20″ Marathon 1200 Carpet Extractor (12 Gallon, 230V)
• Fits many other machines — call 763-535-0770 and we will confirm fitment for your machine.
• Tornado 98167 20″ Marathon 800 (8 Gallon, 230V)

Slotted means it is designed to be secured by a cotter pin passing through the slots and a cross-drilled hole in the shaft. That is a positive mechanical lock rather than a friction one, and it is used where a nut absolutely must not come off — typically on a rotating or pivoting assembly. If your nut has slots, the pin is part of the specification too, and a slotted nut refitted without its pin is not doing the job it was chosen for.

Tightening a slotted nut is different. You tighten to the correct torque and then, if the slots do not line up with the hole, you continue to the next alignment rather than backing off — backing off loses clamping force in a place that was designed to have it. Never force the pin through a misaligned slot.

3/4-18 is a fine thread at a large diameter, so it gives high clamping force for modest effort and strips without much warning. Firm and correct beats hard.

Use a new cotter pin every time. A pin that has been bent open and closed once is work-hardened and will break, usually leaving half of it in the hole. They cost almost nothing.

Fit with clean threads. Zinc plating is a thin barrier, and a nut whose plating has been chewed by a slipping spanner will seize — a seized jam nut is hard to grip because there is so little height to get a wrench onto.

Browse every assembly for this machine on the Tornado 98168 Marathon 1200 parts hub, and see the manufacturer’s range at tornadovac.com.

Frequently Asked Questions

What machines does the nut 30261 fit?

It is fitted to the Tornado 98168 12 Gallon Self Contained carpet extractor and the 98168 20″ Marathon 1200 in all series, and it is shared across many other machines. Call 763-535-0770 with your model and serial number and we will confirm fitment before you order It also fits the Tornado 98167 Marathon 800 (8 Gallon, 230V).

What does the slot in the nut do?

It takes a cotter pin through the nut and a cross-drilled hole in the shaft, which is a positive mechanical lock rather than a friction one. It is used where a nut absolutely must not come off. A slotted nut refitted without its pin is not doing the job it was chosen for.

How do I tighten a slotted nut correctly?

Tighten to the correct torque, and if the slots do not line up with the hole, continue to the next alignment rather than backing off — backing off loses clamping force in a place designed to have it. Never force a pin through a misaligned slot, and always fit a new pin.

How do I order the Nut Hex Jam 3/4-18 Slotted Zinc Plated (part# 30261) or get help?

You can add the Nut Hex Jam 3/4-18 Slotted Zinc Plated (part# 30261) 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.