Caribe C9/Nissan 5hp Combo?

[TooCoys]

I found a Caribe C9 dinghy with a Nissan 5hp two stroke engine on it locally and bought it this week. While it was an extremely good price, and its a very nice dinghy for getting around the marina or visiting friends, I was quite surprised at how slow it was.

With just myself on board, I only got about 6 knots out of it across the lake, and I had to sit well forward and essentially steer with fingertips stretched out behind me. I also ran WOT because anything less and it would squat and get rather sluggish.

I wasn't expecting kidney crushing speed, but 6 knots at WOT and then just barely able to stay there was a little underwhelming.

I've heard that this is normal for small 5hp outboards, but I've seen multiple youtube videos were they seem to be going faster on even bigger boats like 12' v-hull jon boats.

What are some of the things that I can check to make sure I'm operating at maximum potential?

https://www.youtube.com/watch?v=od06z1-zz-M

[liquidice]

That’s about it. Check the angle of the motor relative to the transom. Looks like you’re pitched too close, with too much thrust directing down instead of behind you. You’re a bigger dude. Move around (carefully) to figure out the optimal seating, but consider that there may be too much load to plane. Would a 130 lbs teenager be able to get up? You might want to try. It looks like the “hole” behind the boat is good, but that the boat is not getting up on the bow wave. Make sure Willy is inflated “drum hard”.

How fast do you go at 1/2 throttle?

[TooCoys]

Originally Posted by liquidice

How fast do you go at 1/2 throttle?

Didn't check 1/2 throttle, but its about no wake speed. LOL

I just ordered a cheap ebay tach to see where my rpm's are.

I do know that the pin on the mounting plate that the motor rests on when its down is at least one hole if not two up. It could probably be taken out and "trimmed" all the way down.

[liquidice]

The motor looks and sounds like it’s doing it’s job. The video gets useful for diagnosis at 45 second mark. Look at the angle of the motor hood compared to the angle of the pontoons. I suggest that the prop shaft needs to be angled away from the transom.

It’s pushing itself and the boat too much up and not enough forward.

Also the boat looks to be rated for 15hp, so given the load you may not get more than 6kph from a 5 hp. It also says it seats 4. I’d ride with you but I wouldn’t want to be the 3rd man, let alone the 4th.

[Nicholson58]

I think the Caribe 9 is rated 15 HP. Look at the tag on the transom. We have a Mercury two stroke 15 on ours and it goes scary fast.

[TooCoys]

So then it needs to go up a notch, instead of down I guess...

[TooCoys]

Originally Posted by Nicholson58

I think the Caribe 9 is rated 15 HP. Look at the tag on the transom. We have a Mercury two stroke 15 on ours and it goes scary fast.

It is rated at 15hp max, but a 15 might be too hard to carry on and off the dinghy.

[charris]

We have a C9 and while it has been good, it is brutally heavy. I expect it is the heaviest of its size on the market. One thing to check is the drain plug for the inner hull. You may have water in there giving extra weight. But there is no way that RHIB is going to plane with a 5 Hp

[liquidice]

Also you should wrap the safety switch around your wrist. Usually you fall in:
-when you’re not expecting it
-when people are watching
-when filming

[TooCoys]

Originally Posted by liquidice

Also you should wrap the safety switch around your wrist. Usually you fall in:
-when you’re not expecting it
-when people are watching
-when filming

It’s been wrapped like that for who knows how long, and it’s all broken, rusted, and nasty. It’s one of the things that I need to replace. This was literally the first trip home and I just wanted to get it back before the storm.

Except the storm out ran me.

I follow safety rules, as evident by the life jacket.

[liquidice]

Good news! I just felt obligated to point it out. I figured you for a safe sailor from the horse collar life jacket. Thanks for addressing it. I hate to see runaway dinks!

[bharney]

I have a Merc 9.9 2 stroke with doel-fins and an extended tiller on my c9. With this setup it jumps on plane and is crazy fast with 1 person.

[oleman]

I would expect more but the boat is plowing along like a tug.

I powered a little 8.5' dingy made from plywood with a 7.5 HP Mercury 2 stroke that would skip along the top of swells in San Francisco Bay. In calm waters it planed along nicely. BUT that is 33% more HP.

[liquidice]

Originally Posted by oleman

I would expect more but the boat is plowing along like a tug.

I powered a little 8.5' dingy made from plywood with a 7.5 HP Mercury 2 stroke that would skip along the top of swells in San Francisco Bay. In calm waters it planed along nicely. BUT that is 33% more HP.

In my experience plywood planes much easier than an rib. Even with the hard bottom, the pontoons are slow to plane compared to any comparable hard bottom vessel under the same motor, especially with a 230+ pound captain. I was unable to get on a good plane with a similar dinghy and a ‘65 6hp evinrude on a small flat lake. The same rig strapped on to an old unused plastic paddleboat that afternoon had me planing up easily.

[Dooglas]

I owned a West Marine/Avon 9' RIB for years powered by a 5 hp Nissan 4T outboard. By myself, if I used a throttle arm extension so I was in the front of the boat, it would hop up on a plane. If I sat at the rear seat, if I had gear aboard, or if there were other passengers, it pretty much chugged along.