180 Sportsman Trailer bunk/roller setup pics

[Recoil Rob]

My 180 came on a Sealion Trailer that is less than ideally set up. It has two, 9ft 2x4 bunks that are supported between 2 cross members, one at the transom and the other forward. In front of this is a small bow roller.





The bunk only contacts the hull in the stern, the front 4 ft make no contact with the hull



Advice? I've been thinking I might go to a 4-5ft 2x6 bunk in the rear and then a 3ft 2x4 bunk on the front cross member. I have a set of the Brownell trailer lifts to facilitate bottom repairs/painting, etc and I need the extra 2" in the rear to fit the lifts.


The bow roller is set back from the stanchion end and I can see where the fiberglass has been scraped in the past. That will have to be adjusted or at the very least, a larger roller.



Thoughts about my idea? For the most part the trailer will be used twice a year, once to drive 15 miles in the spring to drop the boat in and another trip in the fall to take it out. I rather stay away from the expense of fitting rollers in the front, but, if that's the best option so be it.

Any advice or pics of your setup appreciated.


thanks,

Rob

 

[DennisG01]

The (2) 2x4's are plenty to support an 18' boat, so no problem there. Getting more hull contact would be good, so as not to rely so much on that bow keel roller. From the pictures, it looks like you could drop the rear support lower and/or raise the front support. If you can move the front supports a little closer together (might be tough with that type of rear support), that will help, as well (essentially the bunks would be closer together at the front than the rear).

Why the wood under the frame? Is there not enough tongue weight? You'll want to address that, too. You shouldn't need wood support to keep the rig from tipping up when entering the boat from the rear. May need to move the axle for that - depending on how much you can move the winch stand... and then ideally move the 2x4's forward as well so you don't have so much 2x4 sticking past the rear of the hull.

 

[Recoil Rob]

The 8x8's blocks are there to get the weight off the wheels & springs during winter storage. I'm replacing axle and springs this year anyway. Might actually be too much tongue weight. I'm figuring the whole rig loaded and gassed will be about 2900, 290 tongue weight would be right. The tongue bottomed out a 300lb bathroom scale but it was digital and it could have been 301 and read Error.

I don't want to lower the rear as I need at least 10" clearance between chines and frame to get trailer lifts in. And I don't think that would make much difference as it's the curve of the chine that's the problem, no way to get a full length one piece support to contact the hull, I think it will have to be 2 bunks/side or bunks and rollers.

I've been looking at pics of 180's on trailer and have not seen one piece bunks.

thanks,

Rob

 

[DennisG01]

For the most part, a hull is a hull is a hull and it's really no different than all of the ones I've set up in the past. Lowering the rear or raising the front supports would definitely help - but if you need the clearance, then that's different. One more thing I just noticed - that rear support has a second bolt in it - preventing it from swiveling (assuming it's similar to the ones I am used to). Take that out and raise the front supports - that should allow the bunks to bend more to better contour to the hull. In the front, if there isn't enough adjustability left, add a 2"x4"x18" spacer.

Are you measuring the tongue weight directly under the ball coupler? Assuming yes... you can use math and physics to your advantage to still use that bathroom scale. There's plenty of google info out there on this so rather than wear out my fingertips, here 'ya go: https://www.etrailer.com/faq-how-to-determine-trailer-tongue-weight.aspx

290 is plenty - you can go less, too. 5% to 7% is standard issue for boat trailers. Doesn't hurt to be a little heavier, though - with a little boat, it's not that big of deal.

FYI... there's no real need to take the weight off the suspension/tires. Certainly do it if you want to, but there's no effective/real world benefit. I have NEVER seen an early failure (I see hundreds of trailers every year) due to compression... and there's the masses of suspensions everywhere... boat trailers, landscape trailers... heck trucks and cars... that sit on their suspension year round. This is more one of those "makes me feel good" things - which is fine. But I'm mentioning this simply so you're aware and if you wanted to not worry about it anymore.

 

[Recoil Rob]

Hey thanks, cool link, I'll give it a go.
As far as the blocks, the existing axel is old and needs to be changed so the blocks will help, but yeah, probably a "feel good" exercise.
BTW, are 2x4 bunks supposed to bend to contour to the hull curvature?

 

[DennisG01]

BTW, are 2x4 bunks supposed to bend to contour to the hull curvature?

Yes, whether 2x or 6x on the flats, they follow the hull. Because that rear support is not pivoting, it's basically creating a 3' length where no bending/curvature is allowed - which then creates less length to where the wood can naturally bend.

I'm looking at your first picture again... it sure looks like the front support is actually lower than the rear. If what I see is right, that's making the issue even worse because it's pulling the front half of the 2x down and away from the hull.