Honda 130 four stroke

[minnie]

Hi

I have a 1998 honda 130 four stroke on a 6 meter tornado.
It currently runs flat out at 28 knots at 5100 RPM.
I plan on using the boat for Watersking and general zipping around. Would I benefit from changing the prop or does the top end and RPM sound about right for a Honda four stroke. (it has been propped for diving before I bought it.)

Thanks

Elizabeth

[Manos]

Flash it with saltX

[swginn]

28kts sounds very slow. You should be getting at least 35/36kts.

The honda 130 hasn't exacty got a reputation for being a quick engine. They are heavy and slow in power delivery but I would still expect it to hit at least 33/34. It sounds overpropped. That engine can spin up to 6000rpm IIRC? Its hard to tell without knowing what prop you're running though?

What pitch/type are you currently running?

[Nick Hearne]

Hi I have a Osprey Viper 5.75 (not a light boat!) with a 100HP 2 stroke Johnson with 13.3/4 X 15" stainless I get 34 knots & a 13.5 X 19" stainless 37 knots! I know you engine is heavy but I would expect better than that!
Nick

[Alan]

According to the Honda marine website, WOT (Wide Open Throttle) range for your engine is 5-6000 rpm. 5100 sounds low, which would lead on to thinking that you are overpropped - too high a pitch prop. However you say that the RIB was propped for diving which I assume means for a heavy load of Divers and kit. In this instance you would generally underprop the boat in a light state so it had the power and ability when loaded. Strange cos although the 130 Honda is a heavy old beast I'dve thought you would get better speed. Silly question but is the prop in good condition (& what pitch is it?) and is the boat kept in the water? I'm thinking mebbe you've got a lot of growth on the hull?

[minnie]

Thanks guys the prop currently on the engine is marked:
D 3x13 1/4x17r don't know if you can shed any light?

The prop is tatty on a couple of blades but not bent.

Really appreciate your help - Elizabeth ;-)

[Arlon]

Plugging those number into a prop slip calculator, you have a slip of around 20+%. That's about twice what one might expect for a planing hull. I would look at the simple things first, bent blade on the prop, dirty hull bottom, mounting height of the motor on the transom, trim angle, etc. My 27ft diesel Panga has better performance than you are getting. I'm also using a 17" pitch prop with a WOT of 4400rpm, I'm running the same 28 knots. The mercruiser and honda also have the same gear ratios of 2:1... Something isn't up to snuff... Arlon.

slip calculator (MPH) good place to get an idea of how things COULD run in a perfect world..

http://www.go-fast.com/Prop_Slip_Calculator.htm

[ADS]

I have a friend who has a Bombard 6.2m and a 90 e-tec, hes getting 35 knots at WOT so with your 130HP even though the tornado is a heavy boat you should see at least 35 knots.

Regards

Alex

[Manos]

Originally Posted by minnie

.......... the prop currently on the engine is marked:
D 3x13 1/4x17r don't know if you can shed any light?........

The prop has 3 blades x 13" 1/4 diameter x 17" pitch.

What make is it? Is it alloy or SS?
Does the engine over rev when you accelerate?
How is the engine mounted on the boat? High/low?
Are any of the blades bent? or has any one tried to fix them by a DIY job (usual thing to save money but you don't in the long run and you need a specialit for the job IMHO)?
Can you change the prop with one 14 1/4 x 17 or 14 1/4 x 19? and see how the boat goes then?

Trying to fix a prop problem is a nasty and expensive experience. Good luck

[Janet and Bill]

We have a 2002 130 hp Honda 4 stroke on a 6.5 m boat. Design speed of the boat is 47 knots and we have maxed it at about 42 knots on a flat sea.

[Arlon]

Originally Posted by Janet and Bill

We have a 2002 130 hp Honda 4 stroke on a 6.5 m boat. Design speed of the boat is 47 knots and we have maxed it at about 42 knots on a flat sea.

What specifically are you using for a prop?? Might help here

[stedj]

i have a 5.5 tornado with a 115 yam 2 stoke 13x16 alloy =36knts 6300 wot 13x23 ss = 44 knots wot both unloaded calm sea im allso looking for a mid prop 4 cuising with 3or 4 crew

[minnie]

Thanks Manos ansering your questions

- It is an alloy prop, probably the original, a bit tatty on the edges of two of the blades, it has not been tampered with repair wise, but seems to be far from knackered
- It does not over rev at all when excellarating
- How can I tell if it is mounted high or low?

Arlon thanks for your help too

Regards

Elizabeth

[Manos]

Originally Posted by minnie

- It is an alloy prop, probably the original, a bit tatty on the edges of two of the blades, it has not been tampered with repair wise, but seems to be far from knackered

OK but if I were you I would take it to a prop repair shop to check it any way. The speeds you say that you do are quite low.

Originally Posted by minnie

- It does not over rev at all when excellarating

Then the bush is OK. So you do n ot lose speed becausxe of a falt there.

Originally Posted by minnie

- How can I tell if it is mounted high or low?

Ask the people who manufacture the boat how high or low the cavitaion plate should be from the end of the hull aft.

Now may be there is something more technical than all this theories and if nothing works and you still get the same speed etc IMHO is best to take the engine to a HONDA (Proper AUTHORISED by Honda) engineer and you will solve (most probably) your problem

Good luck