Lifting a heavy tender without help is dangerous. It creates back strain and ruins the fun of boating. You need a system that does the heavy lifting for you.
For over 35 years, SeaWise Marine has solved this problem. We let you lift heavy dinghies without removing the outboard motor. But before you buy, you need the right fit. An incorrectly sized system can hurt your boat’s fuel economy or trim.
This guide will help you measure your vessel. Follow these steps to ensure safety and easy operation for years to come.
How to Size Your Davit
If you are in a rush, here are the four critical numbers you need:
- Total “Wet” Weight: The combined weight of the dinghy, motor, fuel, and gear.
- Swim Platform Depth: The distance from the transom to the edge of the grid.
- Transom Height: The vertical clearance for the dinghy when rotated upright.
- System Capacity: Choose Manual (450 lbs) or Electric (600+ lbs).
Step 1: Calculate Your Total “Wet” Weight
You cannot just use the “dry weight” listed in your dinghy’s brochure. You must calculate the “Wet Weight.” This is the real weight your davit will lift.
Because our patented davit technology keeps the motor on the dinghy, you must include the engine in your math.
Add these items together:
- Hull Weight: The weight of the empty rubber or fiberglass boat.
- Motor Weight: The weight of your outboard engine (4-strokes are heavier).
- Fuel Weight: Gasoline weighs about 6 lbs per gallon. A full 5-gallon tank adds 30 lbs.
- Gear: Include batteries, consoles, anchors, and life jackets stored inside.
Formula: Hull + Motor + Fuel + Gear = Total Required Capacity
Step 2: Choose Your System (Manual vs. Electric)
Once you have your total weight, you can pick the right model. We offer two main types of systems. Both use our “Vertical Storage” design to save space.
If you are unsure which is best for you, read our detailed comparison on Electric vs. Manual Davits.
| Feature | Manual System | Electric System |
| Max Capacity | 450 lbs | 600 lbs (Fortified to 800 lbs) |
| System Weight | ~100–115 lbs | ~110–125 lbs |
| Operation | Hand Crank (25:1 Gear) | Push-Button (12V DC) |
| Best For | Standard RIBs & Inflatables | Heavy Center Consoles & Jet Tenders |
Need to see them in action? Watch our davit demonstration videos to see how smooth the operation is.
Step 3: Measure Your Swim Platform and Transom
Our systems are famous for “Vertical Storage.” We store the dinghy on its side, tight against the transom.
This minimizes your boat’s Length Overall (LOA). Traditional davits hang off the back by 4 or 5 feet. Our system keeps it tight. This can save you thousands of dollars in moorage fees in busy marinas like Seattle or Vancouver.
Take these three measurements:
1. Platform Depth
Measure from the transom (back wall of the boat) to the edge of your swim platform. We need to ensure there is enough “footprint” for the mounting brackets.
2. Transom Clearance
Measure the vertical height of your transom. When the dinghy is rolled up on its side, the top tube needs to clear any obstacles on your boat (like a railing or window).
3. Structural Support
Ensure your swim grid is strong. It needs to support the davit system (approx. 125 lbs) plus the weight of your dinghy.
Does your boat have a weird shape?
Don’t worry. We specialize in Custom Designs. We make brackets for Sea Ray, Ranger Tugs, Meridian, and Bayliner. Check out our Gallery to see installations on boats like yours.
Why Material Matters: The 316L Difference
You are measuring for a long-term investment. You do not want a system that rusts in two years.
We use only 316L Marine-Grade Stainless Steel. We also use a special “electro-polishing” process. This removes impurities from the metal surface.
- Freshwater vs. Saltwater: It doesn’t matter where you boat.
- Corrosion Resistance: Our steel is virtually impervious to rust.
- Longevity: We have systems from 1987 that are still in use today.
Read more about why 316L Stainless Steel is the best for Canadian and US waters.
Expert Support & Technical Help
We believe in old-fashioned service. When you buy SeaWise, you get lifetime support.
- 7-Day Support: We are open for technical questions from 7:00 a.m. to 7:00 p.m. PST, every day.
- Talk to the Boss: You can often speak directly with our President regarding complex installs.
- DIY or Pro: Whether you install it yourself or hire a local area rep, we are here to help.
Frequently Asked Questions (FAQ)
Can I keep my motor on the dinghy?
Yes. This is the main benefit of SeaWise. Our patented rotation system keeps the outboard motor upright. You never have to lift the engine separately.
Does this block my swim platform?
No. Because the dinghy is stored vertically on the edge, most of your swim platform stays clear. You can still walk, board, and swim easily.
What if my steering cable is stiff?
If your dinghy’s steering is hard to turn, it might be due to corrosion. We sell a stainless steel steering tube to fix seized cables permanently.
Let’s Configure Your Perfect Davit System
Now that you have your measurements, let our engineering team verify the exact specifications for a seamless fit. We can confirm the ideal bracket geometry for your vessel and get your premium 316L stainless steel system shipped directly to you or your local installer.
Contact us today for a custom quote.
- Phone: 604-946-0551
- Toll-Free: 1-866-SEA-WISE (732-9473)
- Email: derek@seawisemarine.com
