Weight distribution on trailer bunks and rollers?

[jhande]

Silly question...
The previous owner didn't have the trailer bow roller setup correctly so after I towed it home I noticed the transom of the boat had slid forward and the keel rolled forward of the roller and dropped down below it. All the weight is now resting on the bunks. I have removed the roller and now am trying to figure out the best way to slide the boat backwards so when I reinstall the roller the keel will rest on it. Yes I'll slide the winch/roller post backwards too.

Question:
The boat is a Tri-hull and I was wondering if there should some sort of weight distribution between the bunks and roller?
I was thinking just sliding the roller up on it's bracket until it contacts the keel but then though might not be good enough since most of the weight will be on the bunks rendering the purpose of the roller useless.

 

[flashback]

I may be mistaken but I believe that the bunks support the boat and the roller is just a guide to keep the boat centered..

 

[jhande]

I was thinking that but if it doesn't have much weight on it how is it really going to guide the keel straight in?

Maybe I'm just over thinking it?

 

[JimS123]

There are 2 opinions in the matter. Old timers have one opinion and newbys and those that don't know better take the other side.

My first boat trailer eons ago was a bunk / roller combo. As a matter of fact it was a "kit" trailer, sold unassembled by the OEM manufacturer. The instructions were very clear. Also, way back then they had a building in town called a "library" that had books on how to be a trailer boater. How to set up a trailer was very clear.

Line up all of the keel rollers in a straight line and set the boat's keel on them. Drop the bunks so they don't touch the hull and then level the boat side to side. Finally raise the bunks to contact the hull, plus a little more. The rollers carry the boat, and the bunks stabilize it.

Been doin it for 54 years and haven't hogged a hull or put a rocker or dent in one yet. The few all bunk trailers I have owned were all upgraded with rollers by me. My boats launch like a dream.

 

[jhande]

Thank you so much for the how to!!!

Humm... Change out the bunks with rollers, I like that.

 

[Horigan]

What brand of trailer is this? Are the roller brackets mounted directly to the trailer frame or on to a large bracket that is shared with the bunks? I ask because my Calkins trailer has a teeter totter system that balances the load between the center rollers and the bunks.

Either way, why don't you just launch the boat and reload it, then move the winch post back to where you want it?

 

[jhande]

Trailer info in my signature.
Yes the center rollers are mounted to the center beam of the trailer.
Can't launch the boat as the trailer & boat are not registered yet (still lot's of work to do on boat) and the water is far away.
Humm... plus right now my truck has an expired inspection sticker and I've already been pulled over twice (yep I need to fix a few things on that too).

 

[JimS123]

Humm... Change out the bunks with rollers, I like that.

That wasn't what I meant. I added a full set of keel rollers and then adjusted the existing bunks as needed.

As a matter of fact, the Owner's manual for my 2017 Boston Whaler specifies that for their boats.

 

[jhande]

That wasn't what I meant. I added a full set of keel rollers and then adjusted the existing bunks as needed.

As a matter of fact, the Owner's manual for my 2017 Boston Whaler specifies that for their boats.

Ahhh okay gotca, me old brain sometimes has troubles.

 

[flashback]

How many rollers do you have to support the hull?

 

[jhande]

How many rollers do you have to support the hull?

Four under the hull with a roller on the winch shaft. I have to try and raise that one since it's under the bow winch cleat.

Beside the roller that was originally under the transom the two in the middle had way to much daylight between them and the keel.

So I'm planning on refreshing and resetting everything on the trailer. Other wise the trailer is in excellent condition. The PO was mounting brand new rims and tires while I was waiting to tow it home from Maine back to New Hampshire.

With all the mountains I had to travel I'm lucky everything made it home in one piece and no accidents.

 

[JimS123]

Four under the hull with a roller on the winch shaft. I have to try and raise that one since it's under the bow winch cleat.

Beside the roller that was originally under the transom the two in the middle had way to much daylight between them and the keel.

So I'm planning on refreshing and resetting everything on the trailer. Other wise the trailer is in excellent condition. The PO was mounting brand new rims and tires while I was waiting to tow it home from Maine back to New Hampshire.

With all the mountains I had to travel I'm lucky everything made it home in one piece and no accidents.

Four keel rollers for a 16 footer should be ideal. The ones that are missing the keel may have slipped down, or maybe weren't adjusted right in the first place. Nevertheless, eyeball the keel itself to be sure IT is straight.

Although the bow roller should ideally be above the bow eye, if you don't have the capability to move it higher it should be OK where it is. In addition to a safety chain, add a bow tiedown with a turnbuckle and that should be just as safe.

 

[jhande]

Four keel rollers for a 16 footer should be ideal. The ones that are missing the keel may have slipped down, or maybe weren't adjusted right in the first place. Nevertheless, eyeball the keel itself to be sure IT is straight.

Although the bow roller should ideally be above the bow eye, if you don't have the capability to move it higher it should be OK where it is. In addition to a safety chain, add a bow tiedown with a turnbuckle and that should be just as safe.

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Thank you Jim!