Hydraulic swim platforms?

Seems like hydraulic lifts work well in fresh water but salt water is their nemesis. Any stories about salt water usage?

Also like to hear more about how the transom is reinforced for a lift. Just what is involved in that work?

Didn't mean to infer that they did not work well in salt water.

On my second boat with a swim platform in saltwater. I didn't shy away from it. When we were looking at our initial requirements our preference was to have the tender on the fly bridge level.

The boat we wound up purchasing was a compromise of initial requirements. We fell in love with the layout - it meant a hydraulic swim platform.

Just like anything else on a boat, when you are dipping components into salt water on a regular basis - be ready for maintenance. In fact, its not just dipping, just being exposed to the salt in the air.

Happy with the one we have.

Mark
 
Just like anything else on a boat, when you are dipping components into salt water on a regular basis - be ready for maintenance. In fact, its not just dipping, just being exposed to the salt in the air.

Happy with the one we have.

Mark

Same as you Mark...
 
Has anyone installed a hydraulic platform on a 90's boat? If so, what work was done to reinforce the transome?
 
Some mid-90's hulls were constructed to handle the weight and stress of a hydraulic platform, some were not. Due to the height and distance between the stringers on the 450DA, I suspect the structure is strong enough, but that is nothing but my opinion. To get a definitive answer, you should talk to the Sea Ray Customer Service guys at Palm Coast, but before you call them, do your research and be in a position to tell them how much the hydraulic arms, the new platform if you are changing swim platforms and the load you plan to haul round on the platform weigh.

If you do need to add some support structure, it is usually just some knees glassed to the top of the stringers and to the transom.
 
Sometimes a picture is easier to explain....the angled wood rising on the right from the stringer to the transom (far right) is known as a knee. The other way I have seen it done is to tie the backing plate of the lift to the stringer with a stainless steel brace using a 35-45 degree angle.
Knee.jpg
 
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We have a Sundancer 410 (year 2000) equipped with a QHS hydraulic swim platform (factory installed) and never had any issues besides replacing the two selenoids.

We are now considering replacing the dinghy for a PWC. What is the weight capacity? Someone mentionned 850 lbs...The BRP Spark is 450 lbs or the GTI is 640 lbs, we like the GTI but it seem heavier. What are your thoughts?
 
I would give Sea Ray a call and ask them. It's not just the PWC it is the aft weight and sea motion that would put the load on the transom. Typically these lifts can lift more than the transom is rated for.
 
One critical buying decision should be ability to get on and off the platform when it is extended. I have a GHS and it pulls away from the boat when lowered. I installed extra grab handles to make boarding safer. I think TNT lifts go straight down. Given different transom designs manufacturer's design may be critical in this regard. I would also point out that many new platforms have integral steps built into them, making it much easier to get back on the boat without having to raise the platform.
 
We have a Sundancer 410 (year 2000) equipped with a QHS hydraulic swim platform (factory installed) and never had any issues besides replacing the two selenoids.

We are now considering replacing the dinghy for a PWC. What is the weight capacity? Someone mentionned 850 lbs...The BRP Spark is 450 lbs or the GTI is 640 lbs, we like the GTI but it seem heavier. What are your thoughts?

Our 2001 dancer with SeaLift is rated 750lbs based on length of boat and performance 8.1s... It will lift 1200lbs but performance would be diminished.

Our dingy with 25hp tohutsu efi weights appox 400lbs. Barely even notice it while underway. Just slightly more trim... We considered the spark seadoo as a fun toy and I am confident there would be zero issues lifting or changing any performance concerns with our 410.

PS I have not even noticed any fuel consumption changes or rpm speed differences with or without the dingy on the platform. The 410 is solid!
 
I installed a TNT platform on my boat 13 years ago. I'm sure being on fresh water helps but there is very little maintenance to it. It has two hydraulic cylinders. I rebuilt both last year. TNT sells seal replacement kits for the cylinders. I started down that route but the kit they sent me was expensive ($160 per side) and had a few wrong seals. I ended up returning the kit to TNT and sourced the seals directly from fastliftparts.com for $38 (both sides). The hardest thing about rebuilding them is getting the new seals on to the piston.

Did you by chance record the seals you ordered?
 
This is what I ordered from Fastliftparts.com

I used the ones I removed as a reference and matched them up using a caliper to measure the the inside diameter, outside diameter, thickness and profile. TNT used different seal kits on various models. Alternatively.....if you have a hydraulic supply nearby you can get the parts you need directly from them. It is a very straightforward job. The only thing that was difficult was installing the new piston seals. The replacements were a much stronger material. I had to boil the seals suspended in water to make them pliable and it was still a finger buster.

Four DPU25-1.50-37 / DPU PISTON U-SEALS
Two ST-75 / RW-95URE-0.750X1.125X0.188
Two U12-0.75-18B / US-90URE-3/4X1X3/16
Two 133 N90 Buna-N Nitrile O-ring Duro 90 (B90133) ordered from: theoringstore.com

Total: $32.08
 
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View attachment 52986 We had a SeaLift installed last spring on our 05 420DA, looked at a few other models but loved the simplicity of the SeaLift design. I believe the cost was close to 19k + 2k to have it shipped up to Michigan + 3k to have it installed by our marina machanic. The marina wanted to sell me the brand that they normally sold but after installing the SeaLift on my boat they they showed my lift to several others in our marina. The main reason we added the hydraulic platform was because we have a daughter with special needs and it is so easy now to get her in and out of the water. We don’t have a large dinghy but it is so slick to be able to use the remote to launch and retrieved it now. Worth every penny !

Looks awesome. Ready to sell?
 
No problem with our GHS in fresh water. One thing you may consider though. GHS lifts have a swim ladder very similar to a SR one and SeaLift's do not
Great Lakes-
Can you share who mounted your lift and approximately the lift and mounting costs?
Thanks,
Mike
 
We would love one, and have always drooled over them but were going to wait to put it on the next boat if it doesn't come with one. Thanks for all the insight guys.
 
I am looking at a 2004 420DA with hydro platform. Can anyone tell me about how far away from the boat the platform is when lowered to the waterline? Also I assume one can stop the movement at any point? The platform was factory installed (as I understand it), but I don't know the manufacturer. Thanks!
 

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