Quick Fix for Spun Hubs
Mon, 12 Mar 2007
Get underway again in under five minutes with a new spun hub repair device.
Although a spun prop hub isn't all that common an occurrence for the individual boat owners, it can happen at any time. The prop could get tangled in a line, clip a log or bite deep into a sand bank. Or maybe the hub is spun too fast as the blades momentarily clear the surface when running a chop. Whatever the reason a prop spins out, that sudden rise of engine rpm and loss of hull speed brings a feeling of dread to every boater.
So what exactly is a spun hub? It is when the rubber or the dry plastic sleeve that connects prop shaft to the prop hub tears loose or breaks apart. This cushion or sleeve provides a layer of protection for the gears and shafts inside the lower unit when the engine is slipped into gear, or the prop clips a piece of debris, or the blades momentarily come out of the water. The protective cushion/sleeve absorbs these types of impacts and the boat continues on its merry way.
However, when the prop hit's a sand bar, rock, boat ramp, stump, or impacts with the water in such a way that causes the prop to exceed the miniscule deflection cushion offered by the hub, the hub's sacrificial process takes over. In literally a fraction of a second, the hub absorbs the shock and then tears or breaks apart, allowing the inner splined bushing, drive shaft, and other critical components in the engine to continue to 'spin' thus avoiding major damage to critical engine components.
Whatever the reason a hub fails, one thing is certain, the boat is usually dead in the water until the problem is fixed and that generally means replacing the prop. Even the dry-sleeve hubs, like the Flo-Torq models used in Mercury, and similar versions used in Turning Point and Michigan Wheel props, can fail. It is always prudent to have a spare prop aboard, or at least a spare hub if your prop uses one. If you have neither, or just don't like changing props over open water, then a new product called Hank Parker's Prop-Aid (www.prop-aid.com)
is a great alternative for emergency use. This unique emergency hub repair device is an aluminum sleeve designed to fit over the end of the exposed prop shaft and into the through-hub exhaust ports of the prop and works with both rubber cushioned and dry-sleeve hubs. The Hank Parker's Prop-Aid installs in just minutes. Simply remove the cotter pin, lock nut and washer. Slide the Hank Parker's Prop-Aid over the damaged hub and reinstall the locknut and cotter pin (not the washer). The fingers of the Hank Parker's Prop-Aid connect the inner hub to the outer hub. This bypasses the disabled rubber sleeve assembly of the spun hub, allowing the prop to apply thrust.
However, Hank Parker's Prop-Aid is not a permanent repair. It simply allows you to get underway in minimal time and at reduced performance. To prevent harm to the lower unit should you strike another object you should not exceed 2,500 rpm and you will still need to repair the prop once you get home. Even so, it is better than paddling, cheaper than towing, and a lot more reliable than a hub that has miraculously fixed itself. Certainly, installing the affordable Hank Parker's Prop-Aid is a lot quicker and easier than trying to pull and replace a damaged prop over open water (especially in the dark-- I know, I've had to do it). No boater should be without one!