tongue weight is 10 to 15% of total weight
If it is too light you will get fishtailing. You will know the tongue is too light if you can lift with without too much difficulty. If this happens then move some weight forward in your boat, such as gas tank, other loose equipment, motor if necessary. You don't want problems on your delivery trip.After you get it home, you can get the boat motor and trailer weighed at a highway weigh scale. Tongue weight can be measured by placing a bathroom scale under the jack foot. (You will need to jack it up first, then support it with a block or something, then reduce the jack, insert the bathroom scale and expand the jack again to lift the weight off the supporting block. It should be 10 to 15% of total weight. After you launch your boat, and depending on the trailer, sometimes the axel assembly can be move back to increase tongue weight, or forward to decrease tongue weight. Remember that adding a spare tire to the front of the trailer will add tongue weight. As well, moving the winch mast forward so that the boat sits more forward on the trailer, will also increase tongue weight. Remember that on a boat this size we are talking the difference of 2 to 6 inches to move tongue weight from balanced, (0 pounds to properly weighted at 250 to 300 pounds.