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Patcheloupe · 14-08-2013, 06:48

Hello,
I just got a Caribe 9' RIB with a 2-stroke 15hp Yamaha outboard. Have been working to adjust trim, mount height, etc for getting on a plane. How long does it typically take you to get out of the 'hole' and into a plane? under what load?
It takes me about 15 seconds with 2 adults in flat calm waters. One adult has to be sitting in front otherwise the bow keeps sticking up (couldn't manage to plane otherwise regardless of setup).
Looking for some comparables to see if this is OK or can be improved.
Thanks!

svHyLyte · 14-08-2013, 07:04

Quote:

Originally Posted by Patcheloupe

Hello,
I just got a Caribe 9' RIB with a 2-stroke 15hp Yamaha outboard. Have been working to adjust trim, mount height, etc for getting on a plane. How long does it typically take you to get out of the 'hole' and into a plane? under what load?
It takes me about 15 seconds with 2 adults in flat calm waters. One adult has to be sitting in front otherwise the bow keeps sticking up (couldn't manage to plane otherwise regardless of setup).
Looking for some comparables to see if this is OK or can be improved.
Thanks!

You might find that adding trim fins to the cavitation plate on your engine will improve your ability to plane. Take a look at (click on) Marine Dynamics StingRay Junior Outboard Hydrofoil .

FWIW...

MarkJ · 14-08-2013, 07:05

One of the best things I have ever bought for the whole boat, let alone just the dinghy, is dolphin fins for the outboard.

All the ads are correct: you plane faster, and its much more stable. the speed droip is un-noticable.

About $60 but worth it!

Wanderlust · 14-08-2013, 07:23

I have a Zodiac 3.1 RIB, so just a little larger than yours. It has a 15hp 4 stroke with the trim fins fitted. With 2 of us it planes effortlessly. It seems almost instant but maybe 2-3 seconds if I used full power. Together we weigh about 180kg plus gear and usually sit partly sideways, half on the seat and half on the float, one with legs in front of the seat and the other behind.

I can't say how much difference the fins made to our setup because they were already fitted when we got it.

**atoll** · 14-08-2013, 07:26

try trimming the leg further forward ,you will need to remove the locking pin that goes through the attachment bracket,and move it one hole forward,easy unless corroded in place

callistov42 · 14-08-2013, 07:40

We have a Caribe 9' with a Yamaha 15hp 2 stroke. With just my wife and I in the boat, it will LEAP up onto a plane. In just 2 or 3 seconds (if I peg it flat out). By myself it is almost scary sometimes. We do have dolphin fins on the engine.

rw58ph · 14-08-2013, 07:51

Sounds like the motor is not trimmed right. Many motors have a setting for trolling so the angle of the motor is high. Just a just the angle/trim of the motor. Also those fins do help.

colemj · 14-08-2013, 10:04

It is also possible that you need a lesser pitched prop. I have seen several new 15hp Yamaha 2-strokes come with a prop pitched so large that it wouldn't plane at all. Dropping 1-2" of pitch made all the difference.

Mark

Patcheloupe · 14-08-2013, 15:14

Thanks you for all the helpful replies.
I already tried adding a doelfin but no meaningful change. I tried changing trims but no real difference. It planes, but takes some time until the bow comes down.
Re Trim - should it be trimmed inwards or outward? Can the height of the engine mount make a difference?

**atoll** · 14-08-2013, 15:53

Quote:

Originally Posted by Patcheloupe

Thanks you for all the helpful replies.
I already tried adding a doelfin but no meaningful change. I tried changing trims but no real difference. It planes, but takes some time until the bow comes down.
Re Trim - should it be trimmed inwards or outward? Can the height of the engine mount make a difference?

inwards to keep the bow down,is the bottom clean,prop undamaged ,carburetter jets clean?

Patcheloupe · 14-08-2013, 16:08

Bottom is clean since hangs off davits. Prop ok. Will check jets tomorrow. It is currently on the first trim hole. Will also try trimming all the way in and report back.
Can mount height play a role at all?
Can u plane so quickly even if sitting alone near the engine and not in the front?
Thanks

**atoll** · 14-08-2013, 16:18

Quote:

Originally Posted by Patcheloupe

Bottom is clean since hangs off davits. Prop ok. Will check jets tomorrow. It is currently on the first trim hole. Will also try trimming all the way in and report back.
Can mount height play a role at all?
Can u plane so quickly even if sitting alone near the engine and not in the front?
Thanks

if the trim is right,i never need to put weight forward with mine,
currently got a 10ft with a 25hp on the back had issues with flipping till i trimmed the leg fwd,ie towards the transom,now will do 50 knots solo!

sy_gilana · 14-08-2013, 17:21

Hi there. There are many issues that can affect this. Most have been covered here already. The fins do work although I don't like them. 2 up on a 9' should leap up onto the plane in two boat-lengths. It sounds to me like that motor is not putting out its best. (Of course this is considering that you are two normal sized people) Lets say that you weigh in at 160Lbs each, then the above should ring true. Your comment that the fins made no difference worries me. Please check that you do not have water between your hulls if it is a double bottom. Could be the bung is out, and as the water drains you get planing.

Next could you please read the pitch off the prop, should be something lik 9 3/4 x 10 1/2 or close.

Also, check that there are no problems inside the engine cover. I have come across many silly things. Is it an Enduro or SW series? If it is Enduro there is not much tuning.

Ok lets say all the above checks out, its time to look under the hood......

Remove the kill cord
Remove the cover.
Observe the linkages on the RHS of the Carburetter, now operate the choke lever, pull and push it, and see that all the pins are engaged in their slots. Sometimes the choke can be 1/3 shut irrespective of push pull position.

Move on to the timing, observe on the engines RHS (Left as you look at it) there is a window in the plastic start mechanism cover. There is a pointer molded into the plastic. Pull the start cord s l o w l y to see the 0 mark, now by hand, turn it back to -5 degrees. Now, look under the flywheel slightly aft of the pointer, and you will see a white pointer, it moves if you rattle the throttle twist grip, (so you can find it) is it lined up with the other line scored in the crankshaft?
Now, put into gear, and open the throttle full but OBSERVE all the linkages on the engine RHS. Rotate the flywheel again and see if the white pointer lines up with the same score, and the plastic line should be about 30 deg.
Now look at the carburettor, open and close the throttle while you do, and you will see a quadrant rotating driven by a linkage, look closely and see if the quadrant actually gets to its stop, ie is the throttle getting to wide open?

If that all checks out we need to re-think....

If you want to give me feedback or ask questions, please email me, I can't check the threads that often...