$60,000 boat on a $200 Trailer – focus on Couplers, Chains, and Winch/Bow Supports – by Bill Nalle

This article was first published in the Southwester Newsletter, editor Craig Stanfield, of the Southwest Chapter of ACBS.  Bill Nalle was awarded the 2017 ACBS-Hagerty Safety Award for the best published article on boating safety.  This is the third segment of the article.

Couplers:

This is pretty simple. Just super-size it, oversize your hitch and ball. The ratings should be marked on the coupler. If you see wear on the coupler replace it. Any wear or damage to a hitch or ball mandates replacement. After a jack knife you need to give serious consideration to replacing the hitch, especially if the tongue shows any bending. What happens is the coupler yields and gets a bit bigger, leaving the opportunity to slip off the ball when going over hard bumps. It won’t be a problem until you hit one of the “roller coaster” bumps at highway speeds and then the trailer pops off. A very bad thing to happen. If you see any bending in the coupler there is a high probability that you have microscopic cracking in the metal. Most couplers are made of cast iron which is different from ductile steel in that it is relatively brittle and forms the microscopic cracks when bent. Fatigue cracking and ultimate part failure begins at the microscopic cracks. If it is bent, replace it before it breaks.

Chains:

You should have two chains, suitable size to the trailer. They should cross each other forming a “bridle” under the tongue of the trailer. If the coupler fails or pops off when you forget to close the hitch, the goal is to catch the tongue and cradle it without it gouging into the ground. If the chains are too loose you can have a trailer digging into the asphalt and that can lead to huge problems. If they are too tight you might bend some metal while turning in the parking lot.

The winch/bow support:

Most classic boats want to be “floated” onto the trailer instead of being pulled up with a winch. Picture this. Your cherished classic boat is floating. Horizontal. The trailer, however, is following the angle of the ramp. Most bow supports are fixed. They contain the winch at the top, and a bow stop. This creates some geometry changes as you pull out, especially in longer boats. With the fixed bow support, once the boat and the trailer come out, there is a foot or two gap between the boat and the bow support, and probably another foot or two between where the transom ‘is’ and where you ‘want it to be.’ The fix is a custom designed, retractable winch/bow support. If you have a really nice boat, build a really nice trailer for her! Otherwise, you’ll be slamming on the brakes of your tow vehicle to hopefully move the boat into position on the trailer.

That does it for part 1 of this complicated subject. In Part II, for another issue, I will cover tow vehicles, axle weights, tongue weights and the balance of the trailer. These topics can be very complex and I hope to shed a bit of light and offer at least a few tips that will help you.


The information from Bill Nalle’s article was posted in three segments. The first segment on axles can be found by clicking here. The middle segment on brakes can be reached by clicking here.

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