New (to me) Hydrohoist

[tomr50]

Bought this hydrohoist a few weeks ago and now preparing it for my slip. I've removed the old bunks and had angle iron welded across the frame to make a deck for my tritoon. I've done a lot of reading about the pressure treated wood and have decided to stay away from it. I've noted a lot of discussion about the width and length of the boards, weight distribution, carpet or no carpet, using UHMW to cover PTW. my head hurts.

My pontoons (Sylvan 8522 FnC RPT w/150 Yamaha ) are 23' long. the distance from front to back of the angle iron support is 10 1/2 feet. So a 16' board would hang over aprox 3 feet. If i got any longer of a board I'm not sure if it would help. I was looking at 2x8,,2x10, and 2x12 . I was leaning towards one 12" board under each toon. or two 8 inch boards.

I also plan to even the tanks up and slide the frame to the centers or should there be more tank in the back to support the stern?

any thoughts on the boards, length width, tank placement etc... I'm going to take some asprin now. Really, I love doing this type of work on and around the boat. It really is relaxing I just want my engineering double checked. Thanks.

 

[alldodge]

What is the length and diameter of the tubes?

Yours was originally setup for an I/O and the center tube is set forward so the outdrive does not come in contact with it. Yours should also need it set forward for the center tank some for the same reason.

Your bunks need to be setup just like your trailer but not as long. Each of the supports should be 2x6 in a V and with a the metal angle under them just like the ones in your pic but placed together. I would say 6 each 2x6 boards in the no more then 12 feet long, if that. Having a board which hangs out past the metal brace will not provide much if any support. Also without the metal under it, the board will sag.

Most of the weight will need to be toward the rear where the motor is and with weight around 500 lbs, and fuel tank holding 24 gallons for another 190 lbs

I'll try to go down tomorrow and take some pics of other tri-toon's on a hydrohoist for your reference.

 

[tomr50]

16 foot. 24 inches. I wasn't planning to make bunks. I was planning to run the boards across the frame where I had angle iron welded on. These pics don't reflect that.

Getting other pics would be great. Thank you.

 

[alldodge]

That size tubes gives you a 6300 pound lift which is plenty

If you lay boards flat this may or may not cause stress or flat spots on the toon, don't know. What I do see is all the lifts here and others I've seen don't let the toon lay flat like on a deck. They also have steel angle under them to keep the boards flat and distribute the load more evenly. The boards will start out flat but will actually only be supported where the beams cross. The first pic is just my quick sketch for illustration.


Some pics

 

[alldodge]

Also did notice the tubes were all kept even, because the drive was well to the rear and away from them. Also most of the over hang is toward the front, because most the weight is in the rear.

 

[bruceb58]

I agree with Dodge. Many hydrohoists where I keep my boat and all have bunks like you would have on your trailer.

 

[nevertoomanyboats]

I'm making the same modifications to our 6600UL lift for our new Sylvan Tritoon. I see some prefab "V" brackets available on line that might work. Obviously wont be able to support then entire 23' of pontoons given the short distance between support frames. How much unsupported pontoon is too much? I would love to see what you fabricate Tomr50. Good photos ALLDODGE, the support angle in your last photo is important, Hydrohoist kit is $2000.