Setting up trailer - The Hull Truth

mbolin · 07-06-2005, 04:03 PM

I have a 19' boat on a trailer that was not originally set up for it. My plan is to cut off the non adjustable bunk supports and replace with the fully adjustable type. Do you guys have any links or info that can help me to properly align the the new bunks to the boat? Is the fine tuning done at the boat ramp by making measurements then launching the boat to make the adjustment? Any advice is appreciated.

krdriver · 07-07-2005, 11:02 AM

Mbolin:
I've gone through much adjusting of boat trailers, but have mostly carried this process out by making adjustments with boat off the trailer. However, you will need at least to look at boat on the trailer to decide what needs adjusting. Guess, I'm not clear. Has the boat been loaded on this trailer and then you could see some modifications were necessary? If the boat has not been on this trailer, you would likely need go with some "Approximate" estimate of bunk placement, length, etc. and then load to see how all fits. Believe you would also need (if you did not already) consider tongue weight on trailer with boat loaded.
You can get a good idea of the tongue weight by loading the boat, making a trip to location with a scale (grain elevator, truck stop) and then taking a few weights. You would need weights of the following: a) complete trailer & boat on scale (not connected to tow vehicle), b) weight of just tow vehicle on scale, and c) Now reconnect trailer to vehicle and pull (or back up) such that just the tow vehicle is on the scale (trailer is off). This reading will be your vehicle weight plus tongue weight. Tongue weight may be calculated by taking c - b. And as mentioned, your tongue weight should be somewhere in range of 8 to 10% of the entire reading for trailer and boat.
The only other method would be if you had access to a hoist and felt confident in the individual's ability to safely lift your boat off trailer which would allow your adjustments. Good luck....

mbolin · 07-07-2005, 11:17 AM

Ok, thanks. I have had the boat on the trailer, but it was obvious that the bunks toward the rear of the trailer were supporting all the weight since the bunks toward the front were not even touching the hull. I'm sure that the way it sits now, there is too much weight/stress on the bow stop and winch.