New Boat Porpoising

60 hp will be well under powered and will be seen as such and therefor reduced in value ...it needs 90 HP .. Mine had a 90 hp johnson 2 st on the back dual batteries and a 45 litre in the nose ...haynes hunter 16 ft ..never had a problem althugh I thought it was balanced like a dum bell with the weights at each end.. yes sure you could re distribute the fuel but what when the tanks are getting empty ....sounds like the motor is too heavy and the boat is too light

 

The boat is too light? I did'nt know they could be.

So your saying he needs a high powered lightweight engine, I think they are trying to make one of those.
If he hangs around 20 30 years we might get this thing fixed.

 

Haines Hunter 16 footer a different boat altogether, a deep vee that could easily accomodate a V4 engine. This is the Signature hull, the various versions of which, none is akin to the old Haines boats. I guess if he just continued designing the same style of boat there'd have been no point of difference.

 

This could be the same hull, I think, as the OP's. Form your own opinion from the way it goes in the chop.

http://www.youtube.com/watch?v=UpFDbNJY-ak&feature=related

 

No frosty he needs to go back 20 years and get a light thing called a 2 stroke with carbs !!! I mean the weight of the engine and the weight of the boat are out of proportion / balance.. well I did till I saw the video .....

Yes seen the video ..I dont call that porpoising ..pourpoising would be on flat water and would be one form of instability ...the boat on that chop was a bit bouncy but about what I would expect..you aint going to get a 16 ft boat to ride waves like its on a bilard table.
I re read the original post " will not take any kind of chop without porpoising" me thinks the new to boating owner is expecting too soft a ride from a small boat .....maybe he is going too fast for the boat /conditions

What we need is the original poster to look at the video and tell us how his compares?? dont like Suzuki .never had any success with them ..always breaking down ..

 

Yes, if he is calling what is happening on that video chop "porpoising", he isn't gonna find a cure.

 

Hi,
Had a look at the video footage, (the Haines 493F) This is how it is for me, The water is like a sheet of glass, You are at full trim, you start to trim out, the RPMS are @ about 4400 rpm, As you start to get close to the first 1/4 on the trim gauge, then all of a sudden the bow starts rising up and down about 300 mm high it will maintain this until you, trim all the way back to full trim, which you can hear the motor start to labor steering becomes very hard. l can be traveling across the lake heading south, Then say l turn to the starboard side new heading ssw, straiten her up, And off she goes porpoising again.
By the way, l use to work in Bass strait, working on scallop boats for allied fishery's.
Hope this helps

Regards Andrew

 

So, if you don't trim so high it doesn't porpoise? Sounds like that's your answer.

I'd try moving some of that weight around and see what effect that has.

-Tom

 

Hi Submariner Tom,
All the porpoising happens in the 4000 to 5000 RPM's range, this RPM range is the range that is the most use, in any small vessel, l should be able to trim from full to the prop coming out of the water, With no proposing, It should not be porpoising on flat water, full stop. And l should not have to keep trimming it all the time, or every time the wind blows from a different direction.
Have just got of the phone from the Rep & Dealer, they are going to remove the 75hp two stroke Merc and replace it with a 60hp EFI four stroke Merc, they are convince it will resolve the issue.
They are re-locating one of the batteries to the port side stern, l have asked if one or both could be relocated to the bow but they said no room

Best Regards Andrew.

 

I would say you've given this boat and dealer every opportunity. 60 hp is going to be unacceptable.

I think I would cut and run at this point. maybe ask for same boat different hull (of course, only if it ran correctly) or my money back thank you very much.

Steve

 

I don't agree with this point. If I want to, I can trim my drives way out and make it bounce between 30-40. I don't consider this a problem - that's why the trim switchs are there On my boat if I over trim and feel it start to bounce it's gentle and I nudge the thottles or trim it in a click or two. Sometimes I hit this zone when I slow down with the drives still out. Depends on the waves and how hard the day has been

I agree with Steve though - you are the buyer and it's your cash. If you don't like the way the boat handles now when it's still "brand new", act fast and change to a setup you do like how it handles on the test drive.

 

Trim is adjusted constantly thats why the button is on the throttle lever.

 

Couldnt agree more Frosty

and many boats will porpoise on flat water but are fine in the chop
and saying "you should be able to trim full out without porposing" is the wildest claim I have ever heard.
Even changing the style of prop would change that

 

wheelybin

I think your expectations may not be reasonable but I'm not really sure I'm fully understanding your situation either. It doesn't make sense to me and that doesn't really matter.

Best of luck.

-Tom

 

You should not have to constantly trim your engine to keep the boat from porpoising. A well designed and rigged boat should not porpoise at all, or perhaps only under a narrow range of conditions.

And you should absolutely be able to trim your boat for optimum speed, which typically calls for trimming the engine up as far as possible without cavitating (aerating) and not have it porpoise.

The only way I would accept this boat if the dealer had to "make" it porpoise through some extreme combination of settings and conditions, otherwise I would consider this, as a brand new boat, to be completely unacceptable.