Lifting a boat off a trailer ... not floating if off.

[McMXi]

Boating season is rapidly approaching so I bought everything I need to replace the carpeted bunks on my boat trailer. I chose a Caliber grey plastic kit from etrailer.com and would also like to clean the hull where it currently sits on the bunks since it's in need of cleaning, waxing and polishing. My boat will never see salt water so bottom paint might be overkill but it's still something I'm considering since it's superior to gelcoat. I've done a fair amount of research into the different ways of lifting boats and I'm not wanting to pull the trailer out from under the boat, just to safely raise the boat 6" to 12" above the trailer for a couple of hours or so.

There are some very expensive hydraulic solutions that would be great if I owned a boat yard and needed to lift boats all day, every day, but for the once a year crowd I found some solutions that involve jacks that bolt to the trailer and have an ACME style thread. Brownell makes some systems but they're also very expensive and supposedly not for aluminum I-beam boat trailers. So I'm thinking about making my own using house jacks and having some form of base sit on the ground that straddles the trailer. Failing that, I'd have some plates that fit inside the web of the I-beam to support the flanges.

As is the way, Amazon and such are flooded with cheap Chinese options that don't exactly fill me with confidence. However, Ellis Manufacturing Inc. who sell on Amazon seem to make decent products and quite possibly Chinese products, but they're not the typical pot metal stuff. I might end up spending an equivalent amount of money building my own lifting system, bu my thought is that the jacks could prove to be useful for other projects unlike the system sold by Brownell which would only serve one purpose. A good set of jacks can be used to raise and support the M6060 tractor for example, or be stowed away in the gooseneck trailer tool box to raise an axle in the event of a flat tire while on a trip.

Early days but I'll be stopping by the boat storage facility today to take a look and get some preliminary measurements to see where jacks might go, current clearance and height required.

If anyone here has any wisdom or experience to share related to this subject I'm all ears.

 

[skeets]

First off if I may ask how large a boat, weight and hull design glass or aluminum, if you mentioned I missed it , type of trailer, inboard , out board, twin or triple and sizes of said motors.
Since you have 2 tractors that will handle the boat weight perhaps web strapping under the hull and lift with the tractors. And then brace with 2x4 framing along the hull making a cradle. I know you said you dont want to remove the trailer but if you are going to replace the runners, having working space is a plus, also gives you a good chance to go all over the trailer checking wiring for brakes, and lights ,cross members springs ,you know all that good stuff. I only mention this, as this is how we did my old 22 foot Bayliner,, yeah I know, we put lots of work into that old gal never got back what we put in to her. And a lot of time fishing for salmon and walleye on the great lakes. What ever you do, just think it through a coupe times

 

[ken erickson]

A family friend was up by my house boating on the chain o lakes a few years back. His boat was fiberglass and had about a 50 hp outboard so not that big. One of his bunks gave way, if I remember the wood rotted and one of the bolts holding it fell out.

Fortunately the fiberglass molded hull had a what I call a "reverse shelf", lol, I am not a boater, that ran length wise from the bow to the stern and enlarged as it went toward the stern.

Long story short, it made a perfect spot to nest a 2 x 4, then my bottle jack fit perfectly from the trailer frame to that 2 x 4. We raised the boat one side at a time , enough to remove the old bunk , I even had some indoor carpet , and replace. We ended up doing both sides that day.

 

[McMXi]

First off if I may ask how large a boat, weight and hull design glass or aluminum, if you mentioned I missed it , type of trailer, inboard , out board, twin or triple and sizes of said motors.
Since you have 2 tractors that will handle the boat weight perhaps web strapping under the hull and lift with the tractors. And then brace with 2x4 framing along the hull making a cradle. I know you said you dont want to remove the trailer but if you are going to replace the runners, having working space is a plus, also gives you a good chance to go all over the trailer checking wiring for brakes, and lights ,cross members springs ,you know all that good stuff. I only mention this, as this is how we did my old 22 foot Bayliner,, yeah I know, we put lots of work into that old gal never got back what we put in to her. And a lot of time fishing for salmon and walleye on the great lakes. What ever you do, just think it through a coupe times

The boat is 21 ft, weighs around 3,500 lb with a single 200hp outboard, but without a full 70 gallon fuel tank. It's a 2-piece fiberglass hull i.e. outer shell and inner liner.

I honestly don't know how it would go trying to lift the boat with the M6060 at the stern and the MX at the bow. I find that idea a little terrifying since it would require a coordinated lift, and lots could go wrong. I also don't know if the tractors could handle the weight. I'm still leaning towards some form of jacking system since I plan to have the boat in the storage unit when doing this where the floor is concrete and nice and level.

I plan to buy new 12ft 2x6 lumber and have the bunk material on and ready to go before I swap out the bunks. I could put the boat in the river at my friend's place, tie the boat up to his dock, pull the trailer out and try to get the new bunks on in the same location, but I still want/need to clean the hull. Lifting the boat a few inches off the trailer, removing one bunk, cleaning and polishing the hull and installing the new bunk seems like it'd go a lot better using jacks.

 

[McMXi]

A family friend was up by my house boating on the chain o lakes a few years back. His boat was fiberglass and had about a 50 hp outboard so not that big. One of his bunks gave way, if I remember the wood rotted and one of the bolts holding it fell out.

Fortunately the fiberglass molded hull had a what I call a "reverse shelf", lol, I am not a boater, that ran length wise from the bow to the stern and enlarged as it went toward the stern.

Long story short, it made a perfect spot to nest a 2 x 4, then my bottle jack fit perfectly from the trailer frame to that 2 x 4. We raised the boat one side at a time , enough to remove the old bunk , I even had some indoor carpet , and replace. We ended up doing both sides that day.

That's called a chine or strake depending on where it's located. Chines make for good lifting points since they're at the outer edge of the hull beneath a vertical load-bearing structure i.e. the outer skin of the hull. Lifting under a chine at the transom is about as strong a lift point as can be found. In fact, looking at the photo below, I might end up only needing two jacks to lift at the stern, and some blocking and a cradle under the bow, unless I can find a good spot under the chine further forward in the vicinity of the ROBALO emblem on the trailer.

Here's my boat as it used to be. The photos are taken from the original FOR SALE add on Craigslist. Hopefully the arrows and labels help.

 

[skeets]

I guess its like skinning a cat, a ton of different ideas and ways to do it. Just take a few pictures how you do it, stay safe

 

[McMXi]

I guess its like skinning a cat, a ton of different ideas and ways to do it. Just take a few pictures how you do it, stay safe

I've experienced a boat-related disaster with a tractor so I'm more than a little hesitant to revisit that possibility. I'll provide more information as this progresses, but it's helpful to talk it out and get input.

 

[Tughill Tom]

Pull it back 4-5ft and lower the front end of the trailer a bit, then block the stern with dunnage( wood blocks) and then lift the front to transfer the weight on the blocks. and pull the trailer out and block the the front under the bow.
To get the trailer back under use the winch to slide it back under and remove the bow block and keep winching it onto the trailer.
I did this every year I owned the Money Pit.

 

[skeets]

I wasnt thinking bow and stern lift that would be scary, I was thinking about across the hull life from the side. We lifted the stern first and braced it then the bow and braced it wide enough to get the trailer out, that thing needed a lot of work, but that only works if you have the room to move around. Keep us posted, Yep I can relate to boating accidents, that where I lost all my guns

 

[McMXi]

Pull it back 4-5ft and lower the front end of the trailer a bit, then block the stern with dunnage( wood blocks) and then lift the front to transfer the weight on the blocks. and pull the trailer out and block the the front under the bow.
To get the trailer back under use the winch to slide it back under and remove the bow block and keep winching it onto the trailer.
I did this every year I owned the Money Pit.

Was that the name of the boat? Money Pit

I've seen this done on YouTube and don't love it but it's an option. Winching a 3,500 lb boat back onto the trailer is an issue for me. How big was your boat?

 

[JasonW]

If you’re not needing to move the trailer after lifting I would consider just using bottle jacks with some type of brace to spread the load against the hull.

 

[McMXi]

If you’re not needing to move the trailer after lifting I would consider just using bottle jacks with some type of brace to spread the load against the hull.

I like the idea of no hydraulics involved if possible, but that's a good idea if I use a screw jack in place of bottle jacks. The trailer would act as a safety device with the boat "hovering" a few inches above it. Maybe some steel bars and plates to locate each jack so that they can't move relative to each other.

 

[McMXi]

I wasnt thinking bow and stern lift that would be scary, I was thinking about across the hull life from the side. We lifted the stern first and braced it then the bow and braced it wide enough to get the trailer out, that thing needed a lot of work, but that only works if you have the room to move around. Keep us posted, Yep I can relate to boating accidents, that where I lost all my guns

Yikes! The boat isn't big with only an 8ft - 4in beam but still. Good thinking but I'm still leary of the loads involved and where the load is relative to the pin on the loader. I'll move this option to plan C at this stage.

I'm liking @JasonW's idea and will see if it's possible given the geometry of the boat as it sits on the trailer. I'd like to be able to lift the boat when needed so whatever I come up with it's not just a one time thing so worth spending time, money and effort to do it right.

 

[Tughill Tom]

Was that the name of the boat? Money Pit

I've seen this done on YouTube and don't love it but it's an option. Winching a 3,500 lb boat back onto the trailer is an issue for me. How big was your boat?

No not the name it just was, always something.
It was a 19ft, IO with V6 mill in it. Came in at about 2500LBS. I just used the hand crank on the trailer to load.
Pro tip wet the carpeted bolsters before reloading it on the trailer.

 

[McMXi]

No not the name it just was, always something.
It was a 19ft, IO with V6 mill in it. Came in at about 2500LBS. I just used the hand crank on the trailer to load.
Pro tip wet the carpeted bolsters before reloading it on the trailer.

Money Pit would have been a good name though. I've yet to experience the need to spend money on the boat. Everything so far has been an upgrade because I wanted it. Not being in salt water and not leaving the boat in the water helps to prevent issues, but some might say it creates another load of potential issues. The way of the world I guess.

So far boat ownership has been a joy for me and I look forward to many more summer days out on the water.

 

[Henro]

Money Pit would have been a good name though. I've yet to experience the need to spend money on the boat. Everything so far has been an upgrade because I wanted it.

LOL...that sorta fits my definition of the term...no doubt in my mind that you will come up with a safe and successful procedure.

 

[McMXi]

LOL...that sorta fits my definition of the term...no doubt in my mind that you will come up with a safe and successful procedure.

We clearly have a different idea of what that phrase means. To me, a money pit is something that we put money into begrudgingly. A car or truck that keeps breaking down for example. A boat that's in constant need of repair.

Putting money into something we enjoy is called an expensive hobby, or a girlfriend, or for some a wife!

 

[JasonW]

I like the idea of no hydraulics involved if possible, but that's a good idea if I use a screw jack in place of bottle jacks. The trailer would act as a safety device with the boat "hovering" a few inches above it. Maybe some steel bars and plates to locate each jack so that they can't move relative to each other.

Or either just use the bottle jack to raise then use wood blocks to set it back down onto. I agree with not working under hydraulics like that.

 

[skeets]

LOL,,, I was asked one time if I knew what the definition of a boat was,, I gave some silly answer, and I was told no, "It is a hole in the water, in to which one throws money" And while that is technologically true it also gives a woman a good reason to get naked, not that would k now anything about that, I just heard
that from the big kids talking

 

[North Idaho Wolfman]

If you built your steel shop then you could hang the boat off the trailer and work on it without any issues!