New Seapro SIB Owner - Advice Needed Please

Vincent Vega · 08 July 2010, 10:23

On Saturday I took delivery of a Seapro 470 with a 45hp Mariner 2007 Engine. My intentions for the boat were to potter around with the grandchildren and also to use it for towing a donut or a water skier.

I took it out this morining on Sale water park for an engine test and it isn't as quick as i'd hoped. At a guess I'd say it's hitting maybe 20 mph. The engine seems to work fine up until about half throttle but once you go past half there's no more acceleration and the engine becomes very noisy. It also seems as though something is slipping and my impression is that it's either something in the engine or maybe the propeller.

I really don't have a clue so any hints or suggestions would be greatly appreciated.

Thanks. :-)

Poly · 08 July 2010, 11:51

I'm guessing you don't have a tacho (rev counter)?

It is possible for the rubber bush inside the prop to slip so the drive shaft spins faster but the prop doesn't (searching the forum for prop bush will probably find reports of others with the same issue - and any easy diagnostic).

I guess the other things that jump to mind where more stick doesn't result in more speed would be if the prop is ventilating - i.e. getting air from the surface if the trim or engine height is all wrong.

Nos4r2 · 08 July 2010, 14:01

45hp? Pics please

Didn't think Mariner made a 45hp since about '87.

Vincent Vega · 08 July 2010, 14:48

Sorry, just checked my invoice and it's a 50hp.

Nos4r2 · 08 July 2010, 15:05

Is it a package you've bought directly from the dealer? If so, take it back and get them to sort it out.

Vincent Vega · 08 July 2010, 15:09

I bought it from a dealer so as suggested i'll contact them and ask for their suggestions. I was just hoping it was something simple that I could fix myself. I may book another engine test on Sale water park and experiment with the trim.

Cheers.

Nos4r2 · 08 July 2010, 16:16

Quote:

Originally Posted by Vincent Vega

I bought it from a dealer so as suggested i'll contact them and ask for their suggestions. I was just hoping it was something simple that I could fix myself. I may book another engine test on Sale water park and experiment with the trim.

Cheers.

If you've got a warranty, don't touch it yourself at all or you'll invalidate it immediately. About all I'd do if I had a warranty is change spark plugs.

John Kennett · 09 July 2010, 11:25

I would double check that the floor is properly assembled and that the keel is inflated to the correct pressure. My first guess from the symptoms is that the bottom of the boat may be deforming slightly as you speed up, putting the prop in disturbed water so it ventilates. If you look over the transom do you notice any visible change when the problem occurs?

By the way, according to the Seapro importers, the 470HD is only rated to 40hp: http://www.seaproboat.co.uk/inflatables.php

Not necessarily relevant, but might be!

Vincent Vega · 09 July 2010, 11:46

Thanks for all your suggestions. The chap at Higham Marine that I bought it from has suggested experimenting with the trim settings so I'm going to take it for a test again on Monday. Hopefully I'll get it performing to my expectations.

Cheers.

hadd · 12 July 2010, 23:53

Quote:

Originally Posted by Vincent Vega

Thanks for all your suggestions. The chap at Higham Marine that I bought it from has suggested experimenting with the trim settings so I'm going to take it for a test again on Monday. Hopefully I'll get it performing to my expectations.

Cheers.

Hi vincent, i have a seapro , the 50hp you have on the back should pull a ringo no problem,start with the engine fully down in the water then just tilt the engine up a bit at a time til you get it right good luck.

Vincent Vega · 14 July 2010, 09:17

Thanks for all the suggestions. I took it out again on Monday morning and after fiddling with the trim settings it seems much better now. It still doesn't feel as quick as i'd hoped but I'm going to take it out again and use a gps to gauge the speed. Out of interest does anybody have any idea what kind of speed I should be getting?

Thanks again.