HydroHoist converted to Pontoon lift

[OK Toon]

My dad had an older '80's model HydroHoist lift that he used to use for his open-bow boat. For about 6 years, the lift would not keep air in the tanks so they would sink after about 3 days. Finally got the nipples in both tanks replaced and the lift holds air perfectly now. I contacted HydroHoist to see if this old lift could be modified to be able to hold our pontoon boat. I was told since this older style had the lower pittmans that we should be able to modify this lift with no problems. So I had some steel brackets made that I installed on the lift and then added bunks. What I didn't take into account was the weight of the boat at the rear and how much lower the back of the boat would sit. So I have created new brackets for the rear bunk supports that will raise the back of the boat higher out of the water (the pontoons were completely out of the water already, but the skeg of the motor was still in the water unless I trimmed the motor up). As soon as I finish buffing out the pontoons on the boat, I'll put it back into the water and test out the new angle of the bunks on the lift.

Here's a few pictures to give some visuals to what I described above.

[curtiscapk]

Nice riggin!

[RcgTexas]

Yep very nice! Even if it sinks again your pontoon could hold it up if you had it tied on.

[babock]

Seems to me like you should move the lift back a bit in the slip and have the boat sit more forward on the lift. Those bunk extensions should be on the front side of the lift...not the back. Pretty sure how that is done at our marina.

[OK Toon]

Seems to me like you should move the lift back a bit in the slip and have the boat sit more forward on the lift. Those bunk extensions should be on the front side of the lift...not the back. Pretty sure how that is done at our marina.

I'd love to move the lift back in the slip. The problem is when the lift was installed back in the 80's, it was welded to the dock frame instead of screwed to the frame. HydroHoist quoted about $4K for new mounting brackets (shipped) and for labor. My new bracket solution was a much cheaper alternative. My other thought was to have someone modify our dock -- there's 6' of walk space in front of the slip. If we could cut into that by 2' to make the slip longer, I could pull in more to the slip thereby getting more of the weight over the bunk brackets.

I contacted the Corps when I thought about adding 2' to the back of the dock (basically just extending the entire dock 2'). But we'd lose our grandfather of where our dock is located -- we are less than 150' from the boat ramp now. That wasn't an issue when the dock was put in so we were grandfathered. They said if I enlarge the dock, I'd have to move it -- that's not an option.

[greghvac]

I have not seen a lift like that. How do you get boat on that. What I'm thinking is you fill the tubes with water so they will sink, pull boat on, then it pump water out. then pump air in. If this how it done how long does it take?

[OK Toon]

Greg, what you don't see in any of the pictures is the control box for the lift. Its mounted to the dock deck. In the control box is a lever, you turn it to "lift/launch" to open the air valves in the hoses that go to the front of each tank - or you turn the lever to "dry dock" to close the valves. There is also a switch to turn the pump on. To lower the lift, you turn the lever to "lift/launch" which opens the valves to allow air in the tanks out. There are large holes in the bottom of each tank towards the rear, that allow water into the tanks as the air is released out of the hoses. Once the tanks have enough water, they sink and the lift pendulums down - safety chains stop the lift from going down past vertical. To raise the lift, the lever is in the "lift/launch" position and this time you flip the switch to turn on the pump which forces air into the tanks and the water is pushed out those holes in the bottom of each tank. When enough air is in each tank, the lift will swing back up. When the tanks are completely empty of water, you'll see large amounts of air coming up at the back of the tanks (right above where those holes are in the bottom of the tanks. Then you turn the pump off and turn the lever back to "dry dock" settling which closes the valves again and the lift remains buoyant.

Takes less than 5 minutes for either function.

Some of the newer models even have a remote control so you can launch your boat then raise the lift while you are gone. Then you can drop it remotely when you get back. Its really hard on the lift to just be left in the down position especially if you have your lift in an area with large waves. Luckily our dock is in a cove that doesn't get much boat traffic.

[Soonertoon]

Got one just like it. Those old J models will last forever . My 23 footer fits great. Takes less than 5 minutes to raise or drop her. The J models have 2 air chambers whereas the rear section drains first and fills last. The first time you operate it , it sorta freaks you out as you watch the front come up while ass end is still in the water.

Just make sure you have the bunks to the correct width so your logs set dead center of the bunks. Also, when the boat is lifted, make sure nobody gets on the boat especially in the back. It will drop and scare the shot out of whoever is on that boat...I know..lol

Hoses, fittings and a new pump every decade and that old lift will last longer than you may own the boat..

[OK Toon]

I was told by HydroHoist that this is an old A model. It actually raises and lowers flat - well other than it being a little unlevel due to the weight of our longer boat. I have two ropes with clips that I have adjusted to the perfect length to center the rear of the boat in the slip. I just have to pull the boat in till the nose cones touch the front of the slip and hold it there till the lift comes up enough to catch the bottom of the pontoons. Then I can let go and just let it come up - centered on the bunks every time. If we have guests on the boat, I tell them to sit still till I have the lift up enough to stabilize the boat, then I stop the pump and turn the lever to "dry dock" so everyone can get off - this puts the deck of the boat level with the dock so its easy for everyone to get off.

I think when we upgrade to a tritoon, I'm going to contact HydroHoist about either adding another tank to the lift or swapping out the 2 we have for a newer larger single tank like they use now - more like a big block tank instead of round tube tanks.

Knock on wood, we haven't had to replace the hoses or pumps on this 30+ year old lift. But I was very surprised that by just changing the nipples to the tanks that this thing works as well as it does after hanging under water for over 6 years - that's a lot of wear and tear on the brackets and lift. So I'd recommend HydroHoist to anyone thinking of getting a lift - even a used one.

[Soonertoon]

It being an A model , which I didn't know they made, did they give you the weight capacity ? I wonder if your boat is over the max as shown by the rear being down. I have a 23 ft suncatcher with a 115 4 str. Yamaha. My boat sets very level. Of course yours may weight more. Nevertheless , you got a unit that has many more years left in it. As a note for the future, you can replace the pump at Grainger Supply for about 70.00....those old lifts are so damned simple. Very few parts and things that move. Too bad they welded it to the dock so you can't move it.

[OK Toon]

They didn't give me the weight capacity (unfortunately), I may have to follow-up with them for that. But I'm sure this was only rated for 2000lbs - which I'm sure I'm slightly over by the time you add motor and fuel. The biggest reasons the boat sits lower in the rear is the back of the boat hangs back beyond the back lift support and even the hoist tanks -- with the motor and 20 gallon tank sitting at the back. This was originally installed for my dad's 18' little open bow Fabuglass boat that used 2 little 6gal tanks (and most of the time we had to take them off the boat to prevent them from getting stolen). I think I'd be fine if I could move the lift back about 2' in the slip, but unfortunately since it was welded, that isn't an easy or cheap task.

Thanks for the heads-up about a replacement pump at Grainger if needed. I'm sure it would be 3x the price if I had to get it from HydroHoist. Have you found a better source for new hoses in the event I need to replace those at some point? I thought I might have to replace them if I attempted to move the lift back in the slip myself (cutting it loose and re-welding it). I wasn't sure if the current hoses would be long enough to reach that extra 2' of distance.

[Bamby]

I just haft to ask...? In looking at the unit from here anyway it appears that adjustments should be possible by loosing the bands on the floats and moving the floats themselves rear-wood some. I'm guessing if they were slid back six inches to a foot the boat would likely float on the bunks level and true as designed.

[OK Toon]

I'm not sure the bands could be loosened up without needing to replace the bands. Here's a few more pics that might show more angles. But I'm not sure only 6"-1' would be enough (as you can see by the pic below of how much the pontoons are hanging off the back of the tanks.

[Soonertoon]

Judging by the pics, you certainly aren't too far back. Hell, mine is in the same general area. I think the weight rating is the key here. My J model is rated for 3000 lb. as far as hoses, again Grainger or Tractor Supply. Not sure how many more years are in those bands...

[OK Toon]

I heard back from HydroHoist and they told me that if the tanks are 24" diameter by 16' length, then it's a 4000lb rated lift. If the tanks are 32" diameter by 16' length, then it's an 8000lb rated lift. I'll have to measure them for sure, but I'm guessing they are 24" diameter tanks. So it sounds like I should be good to go with regards to the weight capacity of the lift. And the guy did confirm this an A-model lift. Doing some other searching on the internet, looks like these old A-model units are only worth about $300-$600 so I guess anything I do to it to make it better for my needs is just saving me $$ from having to purchase a new lift.