problem with inflatable boat.

[Ysi]

Sorry, if is wrong place. I am just a new guy.

I bought SeaEagle 9 just few months ago. I am really satisfied with it. Great boat!!!
Last weekend I tried to use it with 3.5Hp four stroke outboard gas engine, weight it 19 kg. for this boat recommended up to 4 Hp motor with max weight 20kg. I got a problem! When I try to increase speed, even just 15% trust the rear part of boat starts bend to down. The engine starts to submerge into water! The water starts overflow over wooden part of motor mount. Like a some force starts to pull down rear part of boat.
I tried to adjust heights or how is deep submerge the propeller, result is same. The boat was not overload, around of 50% of load capacity.

What is problem, something wrong with the boat or engine? What is solution?

[J3]

Is the boat fully inflated?

Is this the motor mount you're using?

How long is the outboard shaft?

Personally, I would get a smaller motor for that boat.

[Ysi]

Right picture!
- Yes, it is fully inflated or a little bit more for short time.
- Exactly this one!
- Transom heights is 17"
- Propeller size is 3-7 1/7"×7"

[CatBuilder]

Also, dumb question, but is the trim correct on your outboard?

[Ysi]

Originally Posted by CatBuilder

Also, dumb question, but is the trim correct on your outboard?

Sorry, what is it mean?

This boat designed for outboard motor up to 4Hp and 20 kg weight. I have contacted with them. They don't know a nature of this problem.

[rickinnocal]

Originally Posted by Ysi

Sorry, what is it mean?

When the outboard is hanging in the water off the back of your transom, the propellor should be just about vertical, so it pushes straight forward. There is usually an adjustment - typically just a pin that you move from one hole to another - that allows you to trim the angle that the propellor is at.

If the pin is too high, the top of the engine will be leaning forward, and the prop, instead of facing forward, will be facing downwards.

Your problem sounds like it might be the opposite. If the pin is too low - or has fallen out - the top of the engine will be leaning backwards, and the prop will be pointing upwards towards the botom of the boat. On an inflatable, this will tend to make the engine try to fold the back end of the boat under, just like you are describing.

Having the prop too deep can have the same effect due to the long turning arm that gives tending to twist the transom under, but you say you've tried adjusting that already.

Richard

[Easy Rider]

Ysi,
I think you need a transom stern for an engine that powerful and heavy.
I have a 3.5hp Merc 4 stroke and I've used it on other small boats.
I also have a 2hp 2 stroke Yamaha and I'll bet it would work on your boat.
I'd get your money back or trade your 3.5hp for a smaller and lighter engine.
The 2hp Honda should be fine but will make more noise. I think it weighs 27lbs .. the same as my 2hp. The rounded stern of your boat will be sucked down at any speed much over 2 knots. At well under $1000 West Marine has a roll-up model that should take 4hp but it has a transom stern. I just bought one as a dinghy for my 30' boat. When I get it I'll test it for you w 2hp and 3.5hp.
There is no doubt in my mind that your boat has been over rated. Ask them to demonstrate their/your boat for you!

Easy Rider

[Squidly-Diddly]

but that might also create stress that would sudden tear massive holes in the cambers.

I agree, boat is way overrated for 40lb 4hp motor.

I've heard that some small outboard's listed power is LESS than their actual, probably to get around some restriction. Not sure about their weight, but I've heard motorcycles are weigh more than claimed.

[Ysi]

Thanks for your response!

I think all of you right.
The boat is overrated. This is problem.
I have to change a motor, 2.5 Hp more than enough for this boat.
And check installation position.

[Ysi]

Originally Posted by WickedGood

You need a bigger boat

With good equipment like gun machine.

[tunnels]

Simply put you bought the wrong boat for what your needs or exspectaions are !!
The same sized boat with a ridged fibreglass bottom and transom built as one to take an outboard is more what you should be looking for !!
Sooner rather than later you will get sick of putting along at snails pace so bite the bullet and get a boat with grunt and speed and feel the freedom and the wind through your hair !!

[Ysi]

Yesterday, I tried 2.5 Hp with weight 14 kg.
The situation is much better, close to good.

The manufacture of Sea Eagle 9 inflatable boat overrated it indeed!

This boat can hold around 2.5 Hp., weight no more 15kg!!!
They does not has enough strength for more powerful motor and heaviest weight.

I will sale this motor, now.

[jonr]

With all those guns around, someone might shoot back - the last thing I would want is an inflatable boat. Maybe if filled with foam.

[Ysi]

I would like to get another good advise from you and help.
I sold my gas motor.

1. I am going to trolling motor. After review lots of information, found that 30 lbs trust will be good. 40lbs trust will be more than enough.
2. I can't find information what actual weight of it Minn Kota Enduro 30 or Minn Kota Enduro 40

Maybe some body has this information, please send to me. Thanks.
3. How much current they drain? Fully appreciate this information, thanks.


4. And main question is battery. The bigger is better!
But, which size of AGM battery will be enough for 3 hours trip.
Or possible somebody has practical information about how long trolling motor my size runs with your battery.

[tunnels]

Originally Posted by Ysi

I would like to get another good advise from you and help.
I sold my gas motor.

1. I am going to trolling motor. After review lots of information, found that 30 lbs trust will be good. 40lbs trust will be more than enough.
2. I can't find information what actual weight of it Minn Kota Enduro 30 or Minn Kota Enduro 40

Maybe some body has this information, please send to me. Thanks.
3. How much current they drain? Fully appreciate this information, thanks.


4. And main question is battery. The bigger is better!
But, which size of AGM battery will be enough for 3 hours trip.
Or possible somebody has practical information about how long trolling motor my size runs with your battery.

Try this and see what you come up with !!
http://www.minnkotamotors.com/produc...a-charger.aspx