Lifting Boat off Trailer

[76SeaRay]

I need to pull my trailer out to do restoration work on it and gelcoat the underside while the boat is basically stripped of parts, hard tops, and windshields. The boat is a 22 footer. I have two stern tie points that use 3/8 inch U Bolts so pretty substantial. The transom of course is all new so solid. My bow eye for some reason is really low on the bow. Pictures below. I have a gantry crane with two chain hoists so I am thinking about lifting the transom using the two tie points (chain hoist on each) and setting it on pier blocks. Then, move the gantry crane forward and run a 3 inch tow strap under the bow eye to lift the bow off the trailer. Putting the strap under bow eye so that the bow eye keeps the strap from slipping up the bow. Does this sound like it will work safely? Part of my problem is that I only have about 6 inches between the back of the rear rollers and back of the boat. I am hoping that by lifting slightly on the transom ties, I can get the trailer to roll forward a bit to make room to put pier blocks under the transom. I don't even know if the rollers will even roll (part of the trailer restoration) and it also has bunks so I may have to lift it completely off the trailer to get the trailer out.

 

[Chris1956]

If you want to be safe, Put cement blocks under the transom corners and under the bow.

Those stern and bow eyes may hold the weight, or they may fail at any time, as they are not designed for that. if they fail, you will hate it.

 

[Scott Danforth]

actually the bow eye and stern eyes are supposed to be sized by the boat builder to hang the boat.
Here is what I did with the Rogue

an A-frame hoist in the front, a fork lift in the back. Also used a set of jacks once.

to get the front ratchet straps to have some spread, used a chain inside a piece of mechanical tubing.

 

[Chris1956]

Scott in addition to your monster steel support frame I see jackstands under the bow and stern. Why do you need the monster steel support frames?

Also, do you want to bet your life that the stern and bow eyes will hold and not tear out? I sure don't!

Cement blocks hold up houses, easily. They are $2 each. Millions of boats are blocked up with them. What is the issue?

 

[76SeaRay]

Thanks. My plan is to lift it only to get the trailer out like Scott's picture and then block it since I still have fiberglass finishing work to do inside the boat as well as gel the bottom while the trailer is out. I have what I call pier blocks (car cribs) that are 2x4's layered flat stacked up and screwed together. They are about 14 inches wide by 24 inches long. I have 4 stacks that I built to put under my car and truck wheels when I want the car up off the ground (I am restoring 2 cars and one truck). The picture (not mine) shows an example. Mine are wider as I wanted them really stable. I plan to make tapered blocks to put on top to match the angle of the hull.

 

[Chris1956]

You know, you do not need to lift the boat off the trailer, to get the trailer out from under it, right?

Drop the trailer tongue, and stack cement blocks under the stern corners, pad tops with wood. For my 21 footer, I use two 8inch blocks each for the first 2 courses, then a 12 inch block and then two 8 inch blocks, topped with a 5/4" X 6 block of wood.

Now run the trailer tongue up all the way and block the bow with appropriate blocks. You may need to use a v block and a jack to get it to the right height. the boat bow will need to be jacked and blocked a couple of times to clear the cross members.

 

[racerone]

I have taken my 30' boat off a trailer by myself , with blocking and a 5 ton jack.-----No help other than a few small tools.

 

[76SeaRay]

Yeah, I am aware of that but I only have about 6 inches in the back where I could block under the hull (see pic) so there is not much space to block under the transom. The other thing is it will be very difficult, time consuming and wear and tear on this old body to try to keep crawling underneath to jack and move the bow block as the trailer comes out. The bow support would have to be moved about 4 times.

 

[racerone]

??????--Use the winch to pull boat backwards on the trailer !!------Or you tie the boat to a hefty tree or similar.----Pull the trailer forward 18" or so.----Now you have room to block it up.

 

[tpenfield]

FWIW - cinder blocks can be subject to fracture under 'point loads'. So it is a good practice to use plywood (or similar) in conjunction with cinder blocks.

 

[76SeaRay]

Racerone: Good point about using a tree to pull it backwards a little way. I might try that. I guess I would find out how well the rollers work although I don't know how much weight is on the bunks. Guess I could wet the bunks down to make it easier to slide. It's an interesting combination of rollers and bunks. I don't know how long it has been sitting on the trailer before I got it.

Tpen: I know about the structural aspect of the cinder blocks and agree with that issue in orienting them correctly and using the plywood. I already have the car cribs built, I made them in interlocking sections so that I can adjust the height up or down by adding or removing from the stacks. They have been very solid due the flat stacking of 2x4's and have supported my heavy truck and tractor nicely so I will use those.

Since I only have one gantry crane (but with two chain hoists), I could use the tilt the trailer method (and tree ) to get the back supported and then put the gantry crane to the front and lift the bow. Again, the hull is stripped down with only the new stringers, floors and floatation foam in to minimize weight for getting it off the trailer.

 

[JASinIL2006]

FWIW - cinder blocks can be subject to fracture under 'point loads'. So it is a good practice to use plywood (or similar) in conjunction with cinder blocks.

Yeah, I'd be much more worried about a cinder block blowing apart than the gantry crane failing. Especially if nothing was done to distribute the load evenly over the cinder block.

 

[Scott Danforth]

Scott in addition to your monster steel support frame I see jackstands under the bow and stern. Why do you need the monster steel support frames?

Also, do you want to bet your life that the stern and bow eyes will hold and not tear out? I sure don't!

Cement blocks hold up houses, easily. They are $2 each. Millions of boats are blocked up with them. What is the issue?

cement blocks should never be point loaded. they will crush.

I used what I had access to. the 1 ton A-frame was the right width and height
the jack stands are because I spent 12 hours under the boat with a DA removing bottom paint and had to remove the fork lift

When I sprayed the underside, the jack stands were there as a redundant backup, however were not touching as the forklift was back under the swim platform

If the bow cleat and stern cleat are designed to ABYC standards, then I have no problem

 

[racerone]

The boat that I am working had the bow eye installed with a wood block as backing.----Well it was a block when new and it was nothing but powder last year.----Now installed with solid ( no rot ) material.----Lift carefully if you trust the bow eye.

 

[MagKarl]

I didn't trust the bow eye when I did mine. I used big screw jacks in the back and a 4" strap about at the windshield like a marina sling, worked great.

 

[76SeaRay]

I will be checking the bow eye backing block on mine before using it.

 

[mickyryan]

Thanks. My plan is to lift it only to get the trailer out like Scott's picture and then block it since I still have fiberglass finishing work to do inside the boat as well as gel the bottom while the trailer is out. I have what I call pier blocks (car cribs) that are 2x4's layered flat stacked up and screwed together. They are about 14 inches wide by 24 inches long. I have 4 stacks that I built to put under my car and truck wheels when I want the car up off the ground (I am restoring 2 cars and one truck). The picture (not mine) shows an example. Mine are wider as I wanted them really stable. I plan to make tapered blocks to put on top to match the angle of the hull.

View attachment 362228

props for the old paper box scoop on the tunnell ram !

 

[mickyryan]

i took m,y boat apart with 2 gantrys made of wood and harbor friegt remote control winches since i was alone , can confirm the bow eye and the two eyes in transom should easily hold weight of boat mine i was able to even use the cleats since they were through bolted

 

[kcassells]

i took m,y boat apart with 2 gantrys made of wood and harbor friegt remote control winches since i was alone , can confirm the bow eye and the two eyes in transom should easily hold weight of boat mine i was able to even use the cleats since they were through bolted

Yea sure ya did Mick! No pics?

 

[mickyryan]