R31 - Dinghy Motor w/Sea Wise Davit

[TeamWebley]

We are looking at a new dinghy with a 20hp engine to be mounted on a Sea Wise davit on the port side of the swim step. We are wondering if anyone has a 20hp mounted like this and if you have experienced any listing from the weight?

 

[serpa4]

I don't have any information, but want to do the same thing on my C30.
I just installed a 20hp (same weight/size as 10&15hp) on my swim deck to use my 20hp as backup motor if Volvo fails me.
I choose the Tohatsu 20 with EFI and electronic ignition as it was the lightest I could find AND 5 year warranty. It checks in at 94 lbs. The seawise will allow me to hold teh
I also plan to get a AB inflatables Alumina AL9.5 dinghy. It is rated for 15hp, under 10' wide, and is also 2nd lightest (112lbs with locker) I could find that will work with 15hp. To get a 20hp rated dinghy, I'd need over 10' dinghy which is too wide for me.
I think the seawise system is also 54 lbs.
My rear deck will have to hold 54 + 112 + 94 = 260 lbs.
This will certainly put you bow up while on plane. I had my 60 lbs inflatable floor dinghy on the deck deflated and the dingy 20hp motor on the swim step and it was defently bow up with Bennet drop fins installed. Thus, I had 150 lbs on the rear swim platform under way. You will notice the difference/drop in performance.
The 94lb motor with the heavier end of the dinghy and davit on the port side will likely lean to one side. My previous owner moved the 4 house batteries to the starboard side and the two start/thruster batteries to port. When I go lithium, I'll ditch the thruster battery on the port side to make balance even better.

My dinghy fuel will go in the two front seat locker at the bow as they drain overboard and are vented.

I had moved my dinghy in and out of the water and also hand moved the motor (94lbs) from the rear deck to the dinghy in the water. I will CERTAINLY get the davit system like you.

 

[FlyMeAway]

It looks like the Sea-wise system is $5k+ installed. We considered it, but I a Garhauer crane mounted on the swim step can support a 150lb motor and can be had for $1k or under, installed. I'm not sure the Sea-wise justifies the extra $4k, but I'm curious of others' opinions...

 

[serpa4]

It looks like the Sea-wise system is $5k+ installed. We considered it, but I a Garhauer crane mounted on the swim step can support a 150lb motor and can be had for $1k or under, installed. I'm not sure the Sea-wise justifies the extra $4k, but I'm curious of others' opinions...

It is expensive, but the seawise is not just a crane. It is a whole davit system. The parts that allow your dingy to be fitted horizontally on the rear deck. Also the mechanism to allow the motor to pivot from the dingy floating on the water to vertically on the davit system. With the seawise, you never have to take your motor off the dinghy nor ever have to do anything to your dinghy except crank it up horizontally and off you go without ever touching the motor.

 

[FlyMeAway]

It looks like the Sea-wise system is $5k+ installed. We considered it, but I a Garhauer crane mounted on the swim step can support a 150lb motor and can be had for $1k or under, installed. I'm not sure the Sea-wise justifies the extra $4k, but I'm curious of others' opinions...

It is expensive, but the seawise is not just a crane. It is a whole davit system. The parts that allow your dingy to be fitted horizontally on the rear deck. Also the mechanism to allow the motor to pivot from the dingy floating on the water to vertically on the davit system. With the seawise, you never have to take your motor off the dinghy nor ever have to do anything to your dinghy except crank it up horizontally and off you go without ever touching the motor.

Yeah, I'm totally aware! If it were being installed from scratch, it's not a huge upgrade over most other davit systems and likely worth it. But if you're starting with davits already, the $4k difference over a crane is a lot to stomach just for a slightly easier motor install. And, if you look at how they are installed (including the video online of one installed on an R-31), there are still some complications -- not as easy as you describe.

 

[TeamWebley]

Thanks for all of the great ideas!
We corresponded with Andrew Custis at Ranger and he suggested the 9.9 HP engine as we would be about maxed out with what they like to see weight wise with the 20HP engine and davit system. The 9.9 HP weighs 63# less than the 20HP. We're going with the SeaWise because it doesn't require taking the motor off and on the boat.

thanks again -

 

[dgiles]

Thanks for all of the great ideas!
We corresponded with Andrew Custis at Ranger and he suggested the 9.9 HP engine as we would be about maxed out with what they like to see weight wise with the 20HP engine and davit system. The 9.9 HP weighs 63# less than the 20HP. We're going with the SeaWise because it doesn't require taking the motor off and on the boat.

thanks again -

Actually, the 9.9 weighs only 24 lbs less than a 20hp.

 

[serpa4]

Thanks for all of the great ideas!
We corresponded with Andrew Custis at Ranger and he suggested the 9.9 HP engine as we would be about maxed out with what they like to see weight wise with the 20HP engine and davit system. The 9.9 HP weighs 63# less than the 20HP. We're going with the SeaWise because it doesn't require taking the motor off and on the boat.

thanks again -

Actually, the 9.9 weighs only 24 lbs less than a 20hp.

On the websites:
Tohatsu 9.9=94lbs 20hp=94hp
Honda 9.9=92bls 9hp 92lbs. And Honda 5hp is 60lbs.
Mercury 9.9=104lbs and 15hp = 122 lbs

- Which motor is 9.9hp and weights about 30lbs? (the 9.9 weights 63 less) Just curious.
- Also, which 9.9 hp and 70 lbs? Just curious. (9.9 weight 24lbs less)
There are so many outboards out there!!!

 

[dgiles]

Thanks for all of the great ideas!
We corresponded with Andrew Custis at Ranger and he suggested the 9.9 HP engine as we would be about maxed out with what they like to see weight wise with the 20HP engine and davit system. The 9.9 HP weighs 63# less than the 20HP. We're going with the SeaWise because it doesn't require taking the motor off and on the boat.

thanks again -

Actually, the 9.9 weighs only 24 lbs less than a 20hp.

On the websites:
Tohatsu 9.9=94lbs 20hp=94hp
Honda 9.9=92bls 9hp 92lbs. And Honda 5hp is 60lbs.
Mercury 9.9=104lbs and 15hp = 122 lbs

- Which motor is 9.9hp and weights about 30lbs? (the 9.9 weights 63 less) Just curious.
- Also, which 9.9 hp and 70 lbs? Just curious. (9.9 weight 24lbs less)
There are so many outboards out there!!!

Yamaha 9.9 is 87 lbs.

 

[serpa4]

Yamaha 9.9 is 87 lbs
Wow, I'd gladly do 6lbs more for 10.1 hp more.

 

[dgiles]

Yamaha 9.9 is 87 lbs
Wow, I'd gladly do 6lbs more for 10.1 hp more.

Not sure how accurate all these numbers are. Tohatsu is saying their 9.9, 15 and 20 all weigh the same.
Regardless, Yamaha has one of the lightest 9.9's if that is what you need.

 

[serpa4]

Yamaha 9.9 is 87 lbs
Wow, I'd gladly do 6lbs more for 10.1 hp more.

Not sure how accurate all these numbers are. Tohatsu is saying their 9.9, 15 and 20 all weigh the same.
Regardless, Yamaha has one of the lightest 9.9's if that is what you need.

Tohatsu's 10/15/20 are all the same engine. All same bore, stroke, dementions, capacities, etc. Just simple computer programming and of course cost. This is what ALL manufactures do. See Honda, Merc, Suzuki, Yamaha, etc ALL have several HP levels with identical specs, except HP.

Individual choice: 9.9 Yamaha 87 lbs, Limited 3-Year ($2,900) or Tohatsu 20hp at 94 lbs 5-year warranty ($2,900).
Seems simple enough, but I do know Yamaha make a hell of a good motor.

 

[Bobby P.]

I looked into these engines carefully. The drawback to the Yamaha 9.9 is that it is carbureted. I ended up purchasing the Suzuki 9.9 which is fuel injected and comes in at 96 pounds. Fuel injection over a carbureted has many benefits including much better resistance to fuel that has ethanol in it. Ethanol destroys carburetors. It causes varnishing in the tiny jets. Performance is also much better with fuel injection. The Suzuki also comes in a few hundred bucks less. I have had the 9.9 engine for two years and I’ve had zero problems. I’ve also read that with minor modifications it can be tuned up to a 20 hp
I’ll probably get into that at some point in the future.

Good luck!
Bobby

 

[dgiles]

I looked into these engines carefully. The drawback to the Yamaha 9.9 is that it is carbureted. I ended up purchasing the Suzuki 9.9 which is fuel injected and comes in at 96 pounds. Fuel injection over a carbureted has many benefits including much better resistance to fuel that has ethanol in it. Ethanol destroys carburetors. It causes varnishing in the tiny jets. Performance is also much better with fuel injection. The Suzuki also comes in a few hundred bucks less. I have had the 9.9 engine for two years and I’ve had zero problems. I’ve also read that with minor modifications it can be tuned up to a 20 hp
I’ll probably get into that at some point in the future.

Good luck!
Bobby

Ethanol doesn't cause varnishing. It is corrosive and can remove old varnish which can then then plug jets. There are so many misconceptions around ethanol. As long as fuel is fresh, ie under 3 or 4 months, you are not going to have problems. Longer storage can cause problems but not usually. If you do, it is because you have water condensation issues.