Bunks do not support transom since I replaced them last week.

[JiMindy]

I replaced Bunks last week. They are 3" X 8" X8' set on edge, supporting a 21' SeaFox center console. The bunks are long enough, sticking beyond the transom by about 4 - 6" but the rocker of the hull has the bottom edge of the transom about 2" above the bunk! I have twin 90 Mercs hanging off the transom and need the transom to be supported by the bunks to prevent damage. I could drop the forward ends of the bunks, raise the aft end or move them out. I know pictures would help but am not near the boat right now. Appreciate your help. Thanks

 

[bonz_d]

Re: Bunks do not support transom since I replaced them last week.

Guess we have to ask, what changed? Anything? Everything back as original?

 

[Home Cookin']

Re: Bunks do not support transom since I replaced them last week.

the transom itself does not need to be supported (fiberglass boat, I assume). Not sure what a "rocker" is. Professionally rigged trailers have transoms out several inches from the last roller. But if it worries you during storage, use a pair of 2x4 chunks and wedges jammed up in there when you get home.

think about all the boats with motors sitting out unsupported on "sea drive" brackets.

 

[robert graham]

Re: Bunks do not support transom since I replaced them last week.

Sounds like you've got flat bunks trying to support a slightly curved hull, so no way every part of the hull is going to be in contact with the bunks. So if the rear/transom area needs support the most, then either raise the back or lower the front of the bunks to suit. Or you could modify the bunks as they are to provide better support by bolting sections of bunk boards either to the inside or outside rear of existing bunks. Good Luck!

 

[JB]

Re: Bunks do not support transom since I replaced them last week.

the transom itself does not need to be supported

I can't believe you said that, HC. What is to prevent putting a hook in the hull??

 

[bruceb58]

Re: Bunks do not support transom since I replaced them last week.

the transom itself does not need to be supported (fiberglass boat, I assume).

Curious why you believe that.

 

[oldjeep]

Re: Bunks do not support transom since I replaced them last week.

Curious why you believe that.

How do you explain how roller trailers are set up? Never seen one with a roller under the transom.

 

[bruceb58]

Re: Bunks do not support transom since I replaced them last week.

How do you explain how roller trailers are set up? Never seen one with a roller under the transom.

The roller trailer I had on a 27' Bayliner had rollers right at the transom.

 

[Home Cookin']

Re: Bunks do not support transom since I replaced them last week.

I can't believe you said that, HC. What is to prevent putting a hook in the hull??

the strength of the hull. Fiberglass hulls won't melt. You have to have a boat hanging way off the trailer to get a hook.

I can't speak to storing for several years without use; maybe using a boat occasionally straightens them out?

What about sea drives?

Roller trailers seldom go all the way to sit under the transom; you ahve a big problem if the boat shifts forward and the roller ends up behind the boat (BTDT w/a whaler). Look at the whalers: BW says to support the boat on keel rollers and to use short flat bunks more for balance than support.

Now, to clarify, I don't mean no support whatsoever; I mean the vertical plane of the transom does not have to sit directly on support. Whatever support is under the boat near the transom supports it. How near, is the real question. I said "several inches."

I don't know whether the corners on a bunk will dent an aluminum hull on a bouncy road, which is why I restricted my comment to fiberglass.

Seems, too, if OB's can take it, certainly I/O's would even better since their engine blocks (weight) is further forward.

No hook that I know of on my 1988 key West, 17', 70 hp OB, last roller a good foot from the stern.

 

[JiMindy]

Re: Bunks do not support transom since I replaced them last week.

Thanks for the input...didn't consider how transoms are (or are not) supported with rollers. Maybe much ado about nothing. Was just concerned about possible stress on transom with two motors hanging off the stern. I'll drop the front of the bunks about an inch or so to see if that makes me happier.

 

[DBreskin]

Re: Bunks do not support transom since I replaced them last week.

Not sure what a "rocker" is.

Viewed from the side, the amount that the boat's keel line (the bottom profile of the boat) curves upward toward bow and stern is termed rocker. Most frequently used on canoes.

 

[robert graham]

Re: Bunks do not support transom since I replaced them last week.

Maybe remove the rear bunk support bolts, then rotate bunk upwards(with a jack) to be in contact with rear/transom area, re-drill holes, replace bolts?...you'll only be rotating rear of bunks up about 2"....Good Luck!

 

[Home Cookin']

Re: Bunks do not support transom since I replaced them last week.

If the hull has a curve to it, seems you need curved bunks? a short section in the bow on one angle and a longer section in the stern on a different angle, pointing at the low spot in the middle? Or some trailers have flat pads in the bow. Rollers, of course, conform to these things.

BTW I was driving over a bridge next to a marina today and noticed that all the boats on lifts, not one had bunks (lifts) going all the way to the transom. Functionally, that's the same as sitting on a bunk trailer and not going all the way back. These were 22-30 foot boats, mostly OB's.

 

[Boats-A-lots]

Re: Bunks do not support transom since I replaced them last week.

I sort of just asked this question, Im replacing my bunk boards too. I never noticed before if the bunks are loose so when you retrieve the boat the boards can roll to match the boats hull. My option (as I asked in a thread) either use longer bolts to the bunks and double nut them but not tighten to the frame, (so they can roll into the hull shape) or use shims under the 2x6's on the outer side to match the deep V hull. Would this be an option for you? Or is it a bad idea to have the bunks loose?

 

[Home Cookin']

Re: Bunks do not support transom since I replaced them last week.

many different trailer parts are designed to move and fit with the hull; some move as the boat is being launched/retrieved. Seems OK as long as your fittings attaching them are secure and won't vibrate loose while driving.

 

[Boats-A-lots]

Re: Bunks do not support transom since I replaced them last week.

Fl_Richard replied to my post and said "his bunks are tapered". I have a table saw (2 actually) and all I need to do is come close to the angle and taper the 2x6. To the OP of this thread, could you do the same thing?