Process for changing boat trailers?

[briangcc]

Many, many moons ago we used the following process to swap trailers in our stone/mud driveway....

1. Lower tongue all the way possible. This raises the transom up. Block the transom with jacks/wood cribbing/old tires/etc.
2. Now raise the tongue as high as possible. This raises the bow up. Block the keel using jacks/wood cribbing/old tires/etc.
3. Lower tongue down some and carefully start pulling the trailer out from under the boat.
4. Stop to adjust blocking as needed.

To put the new trailer under the boat, back it under, adjusting jacks/wood cribbing/tires as needed. IF you are faint of heart, see if you can do this near a tree you can tie the transom off to.

It sounds like more work than it really is. I helped my dad do this when I was in my early teens....like I said, many, many moons ago.

 

[airshot]

Years back I needed to swap trailers on my 18' Star craft aluminum boat. Borrowed an engine hoist, actually two to be safe. As mentioned in prior post, drop the tongue and shore up transom area, then raise tongue, I added some stabilizing board to the sides so the boat would not tip side to side by just cutting some 2x4 long enough to wedge under railing to the ground. Then hooked up both engine hoist's , one on each side and raised the boat off the trailer, with the transom supported in back and the bow supported by the hoists, I just drove the trailer out from under. Scary part was, I did this by myself....after getting the trailer out, I had to back the new one under without hitting my supports. Not really that difficult, but certainly was scary!

 

[Chris1956]

Gee, I dropped my speedboat on the ground, the motor tilted up enough. I then backed up the new trailer and d/c it from the car and winched it on. The key is to allow the trailer to go under the boat, vs dragging the boat. It also allows the tongue to go high. Of course, my speedboat is really strongly constructed. Slightly built boats could have issues.

 

[ratdude747]

On second thought, such a thing may not work so well with my trailer due to the way the tongue is built. Instead of having a single tube tongue, it has two tubes stacked most of the way down; the lower tube stops short and only the upper tube carries the actual ball receiver. I'll fetch a picture later.

Such an extension bar would have to either have the ball on a riser (to allow the bar to fit under the lower tube) or have a bar small enough to fit inside the lower tube (likely too loose/weak).

Based on that I'll probably stick with the hitch extension I have since it does seem to work and is compatible with the current trailer.

Per further review, doubly no good. In addition to the lower tongue tube, the bump stop/chain attachment point also gets in the way:



Looks like hitch extensions is the way to go with this trailer... Not the most convenient but it's better than having to muck with a new trailer.

 

[airshot]

How much of an extension do you need ?

 

[ratdude747]

How much of an extension do you need ?

Well, 12" plus not using the wrong part of the ramp did the trick

 

[ratdude747]

FWIW, I went boating at a different ramp (as Madison is all tied up with the Madison Regatta this weekend), specifically Duffy's Landing in Jeffersonville, IN. Grivances with the sketchy docks aside (they at least had something!), the ramp was both well roughened and adequately steep... didn't even use or need the 12" extension to get it launched.

I'm calling this thread solved since I found a solution for shallow ramps (and determined it's only 1 ramp with the issue). No need to replace.

 

[ratdude747]

Might have to pull the boat after all... As apparently one of the long bunks is rotten:



The rot tapers off pretty quick but does pass under the transom a bit. The other three by ks seem OK but yeesh...

Maybe I ought to keep an eye out for another trailer after all. Or at least plan on doing bunks sooner rather than later...

 

[Chris1956]

Gee, block up the boat and replace the bunks. Pressure treated lumber and a bit of indoor-outdoor carpet and some stainless steel staples.

 

[ratdude747]

Gee, block up the boat and replace the bunks. Pressure treated lumber and a bit of indoor-outdoor carpet and some stainless steel staples.

Yes, but I'm trying to work out how best to do that given the weight of the boat back there and the close spacing of the existing bunks. I'd have to either support it by the keel with a V-notched hunk of wood or with two blocks very far from the stringers. Maybe somehow use a wood block and a bottle jack on the trailer frame since it's just the one bunk so far. I've seen lots of videos and the like but they're all on lighter boats with outboards...

I'm probably OK to not sweat it at the moment since the load bearing parts seem to be solid (rot is just the leading tip that's well past the rearmost bunk bracket)... or do I need to fix it before driving the trailer across the state for a planned outing this coming weekend?

 

[Lpgc]

Slightly off topic but probably not worth starting a new thread about...

My friend has a Bayliner bowrider with 4.3 Mercruiser, he wants to lower the rollers on the trailer to make the boat sit lower on the trailer to make it easier to launch. It can all be modified using his existing rollers but some of the vertical components of the rollers will need to be cut short / drilled / etc to make it happen. Since he'll need to use various tools and make sure the rollers all contact the boat hull the best place for him to modify the trailer would be at home while the boat is still on the trailer. His questions are how can he lift/support the boat while removing rollers? Can he use an engine crane to take some of the weight or would that damage the drive / transom?

 

[Chris1956]

All or almost all power boats under 40 feet, may be blocked up in the corners of the transom and under the bow. Drop the tongue, put cement blocks and wood under the transom corners. Lift the tongue and put blocks and wood under the bow. Now you have leave to repair your trailer.

 

[Lpgc]

All or almost all power boats under 40 feet, may be blocked up in the corners of the transom and under the bow. Drop the tongue, put cement blocks and wood under the transom corners. Lift the tongue and put blocks and wood under the bow. Now you have leave to repair your trailer.

Thanks, I have copied and pasted your answer to my friend.

Come to think of it I've read similar before. My friend and I didn't know if this would cause a lot of strain on the transom or other parts of the boat. Didn't want to punch a hole through the hull!

 

[Chris1956]

Take a ride to any marina and see how they block boats up. You may even see a boat similar to yours blocked up.

 

[Pmt133]

If blocking it on the transom does cause strain... Well then I really messed up by gutting it lol. This is more or less how every marina I've been to does it. The larger boats typically get railroad timbers supporting the keel and wedges on the transom edges to stabilize it like a cradle. Otherwise blocks and wood. The really fancy fancy ones build cradles for use on the little ones too. Now getting it off the trailer... well that can be fun...

 

[ratdude747]

What if the trailer frame blocks access to the transom? The back bar runs almost directly under such (to the point that the boat doesn't sit on the rearmost keel roller, which instead hits the front of the outdrive near the bottom of trim swing). The bow/winch bar is as far back as it can go... I'm pretty sure this trailer was made for a 17'+ boat and putting a 16' on it is a hack (a hack that's been in use nearly 50 years, anyway).

If I didn't think things would fly apart I'd be tempted to put a rubber/wood wheel chock on a bottle jack and lift against the trailer frame. This bunk runs pretty far (8ft IIRC) so I'll need quite a bit of lift to get it off and resting on something else (might be a keel roller past there, I can't remember). Or bring cordless tools and plan on letting my friend have some fun on the boat during the outing while I try to swap it out in the lake ramp parking lot.

 

[Chris1956]

Gee, loosen the winch strap so you have 6" of slack. Tie the transom eyes to a tree and pull the trailer forward a bit pulling the transom back off the trailer until you can add blocks under the transom corners.

Now drop the tongue and add the blocks under the transom corners, padded with wood. Lift the tongue until the blocks hold the weight and the transom is off the rollers. Block the keel under the heaviest part of the bow and slice the trailer forward. Block behind the trailer cross member, and remove the front block. Repeat for all cross members, and the trailer will pull forward until free. Repeat in reverse for new trailer.

Be very careful not to be under the boat when it is blocked. Push the boat side-to-side when you are blocking it to make sure it is stable.

With a 16 footer, this is not very difficult.

 

[ratdude747]

Have a plan.

I'll replace the bunk in the parking lot this weekend while my friend is driving his cousins around the lake.

Using a treated pine 2x4, stainless 1/2" staples, and new stainless 5/16x1 lag bolts (same as existing, only existing isn't stainless). Old carpet is still in decent shape, so I'm reusing it.

Sound like a plan?

Edit: carpet is wasted in the corner... Right where it rotted. Explains a lot. So I'll see if I can get fresh carpet in time. Also, I'll be at my father in law's all day Friday and he has a good wood shop... I'll whip up some paper templates in CAD and pre-drill the bunks... Ideally all I'll have to do is zip out 4 lag bolts and zip 4 new lag bolts back in?

 

[ratdude747]

For the record, here's my pre-drill template. Took several tries to get a set of board locations that added up. The trailer beams are exactly 35" apart but to reduce slop, the C-brackets are flipped between beams. This is the rear and center mounts... the front mounts do not bolt up (and the plate is off enough one wouldn't get but one of two lag screws in).

Yee haw...

 

[ratdude747]

Got the bunk fabricated yesterday and installed today. The front mount was supposed to be attached after all and is now.

All better:



I used new fabric (raider fabric from Acadamy sports, what I could get on short notice), treated #2 Pine, and stainless staples and lag screws (originals were galvanized and rusty). The lag screws are 1/4" shorter than original, as Lowes didn't have stainless 5/16 lab bolts in 1 1/4" (I went with 1" to ensure they wouldn't go beyond my pre-drill depth). Still plenty of threads holding...

When I got home, I pulled the old bunk apart... the whole length was rotting... JUNK.



Snapped in half when I dropped it by accident...

I'm now having tail light issues, but that'll be another thread as it's unrelated (long story short, Tow Smart "submersible" tail lights... well, aren't!).