Hi Ian,
I can't find a torque setting online ,If it was me I wouldn't over tighten the nut and I wouldn't leave it too loose but would
use low to med strength Loctite to hold the nut in place.
When it comes to the large nut holding the friction pulleys to the main shaft on your Rover Rancher 28166 ride-on mower, the general principle for clutch and friction plate assemblies is that they should be tightened to a specific torque specification, not just "hand tight" or "until there's no movement."
Here's why and what you should aim for:
Proper Engagement/Disengagement: The correct tightness ensures the friction material (cork, in your case) can properly engage and disengage with the opposing surfaces. If it's too loose, you might experience slipping, inefficient power transfer, and premature wear. If it's too tight, it could cause constant engagement (even when disengaged), drag, overheating, and difficulty in shifting or stopping the drive.
Preventing Damage: Over tightening can damage the threads on the shaft or the nut itself, or put excessive stress on the bearings and other components. Under tightening risks the nut coming loose during operation, leading to catastrophic failure of the drive system.
Maintaining Shims and Spacing: The shims you added are crucial for setting the correct spacing and preload on the friction plates. The torque applied to the nut works in conjunction with these shims to achieve the desired friction and engagement.
Most ride-on mower clutch systems (like the one on your Rover Rancher 28166), when the clutch is disengaged, the components that transmit power to the cutting deck or drive wheels should be able to spin freely by hand, or at least with very little resistance.
Usually to find the correct torque specification:
Owner's Manual/Service Manual: This is always your primary source. Look for the specific section on the clutch or drive system assembly for your Rover Rancher 28166. It should list the torque values for all relevant fasteners.
Online Parts Diagrams
Contact Rover/Authorized Dealer: The most reliable option if you can't find the information elsewhere is to contact Rover Mowers directly or an authorized Rover service dealer. They will have access to the official service manuals and specifications.
General considerations when tightening:
Clean Threads: Ensure the threads on both the shaft and the nut are clean and free of rust or debris.
Threadlocker (if specified): Some manufacturers recommend a specific type of threadlocker (like Loctite) on critical fasteners. Check your manual for this.
Torque Wrench: Always use a calibrated torque wrench to ensure accurate tightening. The assembly should be tightened to spec and not have rotational play between the friction material and the pulley.
"Rotational play between the friction material and the pulley" refers to unwanted movement or slippage between these two components when they are supposed to be firmly engaged and acting as a single unit.
Cheers
Max.
