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where2 · 08-26-16, 10:07 PM

Nice find. I'm partial to floaty things, floating docks and boats...

I've had a DIY boat lift working on similar principles under my 15' Boston Whalers since 1999. It will lift either my 1985 15' Sport (70hp outboard), or my 1995 15' Rage (115hp OMC Jet Drive). It works similarly to your SportPort for your PWC, and docks the boat entirely out of the water. Between my father and I, we actually have three different DIY floating boat lifts, all use the air displacement lift system.

Contrary to what Jeff thinks, the black HDPE float tanks are incredibly UV tolerant even in South Florida. The sinking part of my lift sits on two black HDPE roto-molded float "tanks" rated for 1800lbs lift per unit. Considering my whaler lift framework is primarily 3"x8" pressure treated lumber, with 2x8 pressure treated decking, I need all that displaceable buoyancy, and a large amount of fixed buoyancy under the lift. Since my whaler lift was DIY, my father and I had to experiment with different blower units, and finally settled on a Dirt Devil Shop Vac motor designed to be removed from the vacuum and used as a backyard leaf blower. They work surprisingly well. The HDPE tanks were commercially available items, but even the seller of the tanks didn't know what to use for a blower back in 1999. We eventually told them what we used to help others...

The largest lift we've built has two 2400lbs tanks, and two 1800lbs tanks. It picks up a 20' Edgewater center console with a 150hp 4-stroke. The framework under that one is all 6061-T6 aluminum with 316 stainless hardware, because we're on salt water. When lifted, 100% of the hardware and framework is above water, on all our lifts. Salt water is harsh on metal, and I have always been amazed how many lift companies design lifts with metal parts underwater.

08-26-16, 10:07 PM	#6
where2 DIY Geek Join Date: Apr 2013 Location: Sunny Florida Posts: 401 Thanks: 74 Thanked 83 Times in 73 Posts	Nice find. I'm partial to floaty things, floating docks and boats... I've had a DIY boat lift working on similar principles under my 15' Boston Whalers since 1999. It will lift either my 1985 15' Sport (70hp outboard), or my 1995 15' Rage (115hp OMC Jet Drive). It works similarly to your SportPort for your PWC, and docks the boat entirely out of the water. Between my father and I, we actually have three different DIY floating boat lifts, all use the air displacement lift system. Contrary to what Jeff thinks, the black HDPE float tanks are incredibly UV tolerant even in South Florida. The sinking part of my lift sits on two black HDPE roto-molded float "tanks" rated for 1800lbs lift per unit. Considering my whaler lift framework is primarily 3"x8" pressure treated lumber, with 2x8 pressure treated decking, I need all that displaceable buoyancy, and a large amount of fixed buoyancy under the lift. Since my whaler lift was DIY, my father and I had to experiment with different blower units, and finally settled on a Dirt Devil Shop Vac motor designed to be removed from the vacuum and used as a backyard leaf blower. They work surprisingly well. The HDPE tanks were commercially available items, but even the seller of the tanks didn't know what to use for a blower back in 1999. We eventually told them what we used to help others... The largest lift we've built has two 2400lbs tanks, and two 1800lbs tanks. It picks up a 20' Edgewater center console with a 150hp 4-stroke. The framework under that one is all 6061-T6 aluminum with 316 stainless hardware, because we're on salt water. When lifted, 100% of the hardware and framework is above water, on all our lifts. Salt water is harsh on metal, and I have always been amazed how many lift companies design lifts with metal parts underwater.