Lifted my boat off the trailer with garage rafters

[NateD]

Thought I would share in case anyone else is looking for a way to get the boat off the trailer. I wanted to do some work on my trailer over Memorial Day weekend at a workshop that was about 150 miles from home. Original plan was to tow the boat and trailer up there, and anchor the boat in a nearby lake for the day while I worked on the trailer, but my tow vehicle (Grand Cherokee) was overheating. If I could get the boat off the trailer I could easily tow just the trailer with my car. I had read posts on this forum about sliding the boat off the trailer onto the lawn, but he had a tilt trailer which made it easier to get it back onto the trailer. That wasn't going to be an option for me.

After a significant structural integrity test (I tied a rope onto a rafter and hung from it), I decided that if one rafter would hold 200 lbs without any problem, then 1,100 pounds distributed across 8 points shouldn't be a problem. In the end I didn't distribute the weight over as many rafters as I had planned, but everything held.

We centered the trailer as well as we could in my 1.5 car garage built in 1980 (and leaning a little already, but fixing that is project for another day).



Then we wrapped two 30 foot straps around the rafters, ran them under the boat on either side of the keel, tied loops into the other end of the straps. We had another strap wrapped around two rafters on the other side of the boat, and attached one end of a 1,250 lb come-along onto the strap, and the other end was attached to the straps running under the boat.









After a little winching we discovered a flaw in my previous stress testing. I had only considered vertical forces, I didn't test lateral forces. Because we had the straps wrapped around two rafters (to distribute that vertical force), they were pulling the rafters toward each other. So we cut some 2x4s and nailed them between the rafters. We also decided to add a little extra support under the come-along rafters and placed extra 2x4s between the rafters and the floor.

A few tense minutes later, she was in the air and the trailer was in the driveway.




We stacked some 4x4 lumber under the keel and let it down far enough to take most of the load off of the garage. Here is a picture of why I really wanted to do some work on the trailer.



And here was the end result. Old rollers off, new board under the keel, new bunk boards with carpet. I need to pull the keel board off when I sand blast it, so I didn't put the carpet on that yet.





Both of my helpers were skeptical at the outset, but after we did the minor reinforcing, and the boat was actually up in the air, everyone agreed that the garage (and gear) were holding the weight well. But my guess is everything looks like it is holding up fine right to the point that something breaks. I plan to do it again when it's time to sandblast and paint the trailer.

[mrb]

Nice job. 

  I did the lawn thing and it works fine.  Did scare wife to no end though.   Next time I will do as you have, only in a barn.

Melvin

[B.Hart]

  I did the same thing in my shop(30x30x12h) .I lowered the bow and put a55 gal drum under the stern, then lifted the bow with a strap to get the trailer out, then blocked the keel and left the strap to balance it. I also had already had added 2x8's in the rafters for lifting things.    BILL

[Craig Weis]

For my 19 I just tied the two stern cleats to the trailer and lowered the hull bunks out of the way. She sat on her keel, resting on two? or three? [I forget] of the trailer's four hard rubber rollers.

After I finished the hull 'up there'...

Then I jacked up the hull bunks and 'hung' the 19 from these to do the keel.

To bottom coat the lower hull...

The best thing about doing this is 'No strap marks' to clean, or work around, or paint around.

If you look at my boat pictures you'll see that I sawed to shape, and Marine-Texed a 6mm aluminum plate to the bottom of my flat keel so I could bounce over rocks without chipping the glass.

I did saw off the keel bunks because these bunks are not necessary and in the way and the boat won't care if the keel has bunks on the side that don't touch the keel.

I simply winch her on to the trailer from the bow eye and she floats right in between my two orange fiberglass driveway markers on the back of the trailer that the hull lighty touches when positioned correctly over the trailer.

The hull remains trapped within the cure of the hull bunks and is not able to 'jump out', but can be floated out.
skip.

[Potcake boy]

Nice job Nate, I also unloaded mine onto tha lawn way back when to do tha bottom - gee that was a long time ago, and I did many other crazy unorthodox things then as well.

Is that a TDI hooked up to your trailer? If it is, it may well tow your boat. Towed a 4X8 U-Haul loaded to the brim from Florida to Maryland with my 2002 TDI - no problem.

Ron

[NateD]

Potcake -

    It's not a TDI, bmw 328i. It will tow the trailer and boat, but the trailer hitch is bolted onto the sheet metal that makes up the bottom of the trunk, so it makes me a little nervous. I towed the boat 150+ miles with that car last year, but I prefer to pull it with something that has a hitch attached to a frame.

[Craig Weis]

NateD, Make a sandwitch with some flat bar on top of the trunk's sheet steel but under the rug.
Bolt through the flat bar [3/16" or 1/4" x 2 " wide.] and back into the bolt holes in the hitch.
It's all about spreading out the weight. It's not the weight. Big-O-Flat washers don't do it.

By using some flat bar to sandwitch all this together you'll more then redouble
the resistance to tearing the sheet steel floor of the BMW trunk.

I made a hitch for my '70 Ford Maverick in college to flat tow my jeep back to Glenview, Illinois rolling on all four wheels from Normal, Illinois.

I did a hard left at too much speed and the jeep whipped my rear end out of the apex of the curve and through a ditch. I never stopped~just kept going~and the hitch held up fine. No big deal.

Just remember when towing anything and your engine feels as if it's straining, it is, and what takes a beating are the valves and seats in the head. Valves get hotter and stretch. Seats get hotter and are pounded to death [read "to a leaky condition"] in the head.

So drive her like you have a raw egg between your foot and the gas pedal to reduce the heat. RPM's drop allowing the valves more time to sit on the seat and transfer a little more heat to the seat and hence to the cooling water. Removing this heat and saving the motor. 

My sailing buddy has to figure out what he wants to do...buy a junk yard engine [$1800 with install, or a factory rebuilt $2700 with install and warentee] for his Honda CR-V because he broke a timing belt and the bent enough valves to have nearly two 'zeros' and a 'almost' and one good cylinder on a compression check. Honda's are pretty soft if pushed past the design criteria.
But then again that's typical of Jap stuff.

Two dozer's pushing dirt during the Edens expressway rebuild in Chicago. Turn off the Cat and knock, knock, knock...you'll have the rest of the summer before renewing the bearings is advisable. Turn off the Jap one and knock, knock, knock...you'll have three weeks before renewing the bearings is necessary. So I guess down-time dosen't cost anything. As long as the purchase price is cheap.
skip.

[Potcake boy]

Potcake -

    It's not a TDI, bmw 328i. It will tow the trailer and boat, but the trailer hitch is bolted onto the sheet metal that makes up the bottom of the trunk, so it makes me a little nervous. I towed the boat 150+ miles with that car last year, but I prefer to pull it with something that has a hitch attached to a frame.

Sorry about that Nate I guess my vision is failing me - I could swear that was Elvis I saw at the restaurant.

I towed my 16 with a Mitsubishi built 1.5 litre Dodge Colt.  Being of a unibody type construction the hitch was mounted in the same fashion as your car - never any hint of a problem.  You should be able to use your BMW with full confidence if you wish.