2014-8hp Outboard

S

stuartdmc

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Joined
May 1, 2006
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21081
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I recently purchased a Yamaha 2014 8hp form a gentleman in FL. He bought it new in 2015 and sold it to me a month ago, I had it shipped out to me in California, I put it on my 9ft ribbed Avon. The engine will not get the dink on plane!! I thought that it would have shot out of the water!! but no it wont. Is it the engine? Could it be the jet's do they need to be adjusted or changed coming from coast to coast? is there any difference in climate? I would not think so? There is one year left on the warranty is there something the dealer can check like the high speed settings?

Open for suggestions. Thanks.
 
It could be the engine or maybe even the wrong prop. I'd take it to a Yamaha dealer to have it checked out.
 
Which AVON RIB? I see a "260" at 8-feet with an 8-HP rating and a "310" at 10-feet with 10-HP. I'm no expert, but it seems to me 8-HP should plane it. But, I don't think it'd be a sudden jump.
 
Where are you sitting in the RIB? If you are all the way in the back, there's a good chance you won't get on plane. Try to center yourself in the boat and it should plane easily (assuming the engine is running properly).
 
It is a 310 max engine is 10HP. I am about 240 lbs and seat in the center on the bench seat. I had two other people at the dock look at it and said that that engine should push that boat with no problem. They even drove it less weight then me and it would not get on plane.
 
Did you untie it from your boat?

Sorry couldn't resist I can't imagine why it would plane. I had an older vision of this motor and while it was never a speed demon it certainly could boat my last heavy wood floor and my current dink up on plane with out much difficulty!
 
lol..
I did!

I called up the dealer, he said to check and make sure that the engine wasn't put on the boat without making sure that the cavitation plate was even with the lowest part of the hull. Which I know all about from other boats I’ve owned. He said that if it is lower by even an inch it can cause drag where the engine can’t reach its top speed. Sounds right to me? Right. Well give it a try and see, stay tune.
 
I have a 4hp on a 9 ft rib and can get on plane. I have to put the gas tank in the bow and I have to slide up to midway where my hand can just touch the throttle. Also can get on plane with my 8 year old in the bow. Is it possible your prop is shot.
Al
 
Will the rib get on plane with a different motor? If a double hull rib there could be water in between the hulls.
 
Will the rib get on plane with a different motor? If a double hull rib there could be water in between the hulls.
 
There's no water in between the hull first time Ive put the boat in the water this season, as far as I know the only engine that I know has been on the boat is the 8hp Yamaha. the person I bought the engine from sold it to me because he could not get his 13ft. Boston Whaler on plan with the 8hp. Now in that case I would say the engine was undersized. Could anything have happen to the engine if they get pushed to hard?
Just a thought.
 
Well, No one is saying that its the engine so it must be the way the engine is mounted on the rib dink. I thought for sure it was the engine. any thoughts?.
Thx.
 
Yes. Find out what propeller is on it. It may be marked with Diameter and Pitch, or you may need to back into it using a Part Number. Then see where that prop falls in the collection available for your motor. There may be a lower pitch available.

I'd agree that 8-HP is low for a 13-FT Whaler. Rating is 40-HP if I recall. A friend had one, 9.8 MerC two-stroke and it would plane with two light persons aboard, but a waste of that quality boat's capabilities. A buddy of his came up with another 13 Whaler, no motor. The motor he "happened" to come up with was a 3-cylinder OMC two-stroke with 55-HP. Probably around 55-MPH too...

Am I correct thinking this Avon has an inflatable floor? If so, is it fully inflated?

Is this a four-stroke? Wonderful motors, but more weight aft and a little less grunt out of the hole than a Two-Smoke.
 
How much does the RIB weight? I don't know much about engines but it seems to me if you have a year left on the warranty why are you struggling to find the answer.....bring it to a dealer and let them figure it out.
 
The Avon is a hard bottom inflatable, weighs in dry at 135Lbs.

quote:
Originally posted by j-d

Yes. Find out what propeller is on it. It may be marked with Diameter and Pitch, or you may need to back into it using a Part Number. Then see where that prop falls in the collection available for your motor. There may be a lower pitch available.

I'd agree that 8-HP is low for a 13-FT Whaler. Rating is 40-HP if I recall. A friend had one, 9.8 MerC two-stroke and it would plane with two light persons aboard, but a waste of that quality boat's capabilities. A buddy of his came up with another 13 Whaler, no motor. The motor he "happened" to come up with was a 3-cylinder OMC two-stroke with 55-HP. Probably around 55-MPH too...

Am I correct thinking this Avon has an inflatable floor? If so, is it fully inflated?

Is this a four-stroke? Wonderful motors, but more weight aft and a little less grunt out of the hole than a Two-Smoke.

Click to expand...
 
Any chance it's still attached to the trailer ?
BOB J
 
quote:
Originally posted by Bob J

Any chance it's still attached to the trailer ?
BOB J

Click to expand...


Couple fisherman tied up at the boat ramp, got the trailer, and started winching the boat out. They were talking about how great the boat ran going out and how slow it was on the way back.

Pulled the trailer out and noticed the anchor line going out into the water. They'd dragged anchor all the way back.
 
My 2004 8hp Johnson gets my 8ft Livingston (solid fiberglass) dinghy on plane no problem as long as I'm the only one in it, and I sit amidships with a tiller extension. I'm about 200lbs and the boat weighs around 150lbs. The Livingston is a twin hull design. Similar power to weight ratio to yours...
 
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