Zodiac acti V not planning

[paintman]

Originally Posted by BCRyan

Thanks for all the suggestions since I do has some rpm to play with I think I will try a different prop size and see if that helps.

I have some other guys in another forum suggesting to try trim tabs either the nautiicus smart tabs or the maxi-marine lifters. I’m being told that these tabs really make a huge difference in helping to get up on plane.

Anyone have experience with these?

Thanks again

You've already tried a foil on the engine without any success.

Your boat & engine combo is currently set up to give best performance with one person on board.
Your drop in WOT with more on board is entirely to be expected & your rpm says your prop is wrong for this new load.
Changing your prop is going to be easier than drilling a load of new holes in your transom.

[Limecc]

Here's the manual, I'm sure you followed it already.
https://www.manualscat.com/en/zodiac...-acti-v-manual

[Wazzajnr]

Just a thought, just because the engine is new doesn't mean it's running correctly?
Loss of a couple of hp due to a carb blockage or bad plug etc could easily make the difference.

[Flamair]

Slightly bizarre issue. I have a Ysm 3.1m airfloor and a 2005 8hp Yam 2 stroke.

With myself and my lad we're about 170kg. I sit on the RH tube and he either on the seat or more usually LH tube midway. The tank is central but toward the bow (12l). In the bow I haveva bow bag, grapnel anchor, warp, chain. Assorted tools and food/drinks for the day.

On the lake I have no problem planing at all. In fact 2/3 to 3/4 throttle has it jumping forward like anything!

Given the above, I feel you should be getting on plane fairly easily, unless you both weigh a lot more than average, or you're carrying a lot of gear/stowing gear in the wrong place

I've been sibbing for years, but consider myself pretty poor at working stuff like this out. I agree about the motor check. I had a new 4hp in a 2.8m Sevylor years back hat had fuelling issue. I was a bit disappointed with it one up. Had the engine checked and the dealer rang to ask if I'd felt the performance was off. I said it had felt so.
Turned out there was some fuelling issue with it (not sure what). What i do know is the Sevylor flew one up with kit for a day out after the mech. had sorted it.
Worth a shot I think.

[BCRyan]

From what I’m learning from all of you I’d better get myself a good pressure gauge and ensure my pressure is right before I go and do anything drastic.

[Fenlander]

That would be my inclination as its a basic requisite.

[lightning]

As above really.

l've got a Zodiac 285s with a Tohatsu 9.8 two stroke.

One up the boat goes like a rocket (well, relatively speaking) and will achieve around 20mph
Two up she's a little slower but planes almost instantly and tops out around 18mph

l used to have a Mariner 6hp, and with that engine the boat planed easily one up, achieving around 14mph
Two up my wife had to get to the front of the boat and then we'd get on the plane up to a similar 14mph.

l've got no trim tabs etc but the 285s does have a solid floor with an air keel.

l did try a higher pitch prop with the 9.8hp
With the higher pitch prop the rpm for any given speed is around 500rpm lower.

The boat takes a bit more time to get on the plane, as in it's not instant.
WOT is 5,000rpm as opposed to 5,500 rpm with the standard prop.
Engine handbook says WOT should be 5,000-6,000 so that's a little low.

The only real advantage is at trolling speeds on the canal, where the engine is a bit smoother with the higher pitch prop. Possibly because it's working a bit harder so vibrates less.

[BCRyan]

Thanks for all the brainstorming you have all been doing to help me out here I have a little bit of an update but still problem is not solved.
Finally had a chance to try the boat out again this weekend, I ended up trying some Bennett trim tabs because I was able to get ahold of them for very cheap and figured why not give them a try.. well sure did help me get on plane a whole lot quicker with just me in the boat but did not help at all with another person with me.. I have yet to try a different prop because I could not get ahold of one before my trip to the lake, I will try that when I get back there at the end of July.

Air pressure is confirmed good. Two different gauges same reading .. 11.2psi in floor and 3.4psi in tubes.. I even tried to over inflate by a full psi to see if it helped and no difference… and psi was taken while in the water


I have tried putting the passenger in multiple spots in the boat with no luck. I actually find that it pushes more water with the bow when I have someone right up on the bow.. .

As for weight in boat I’m about 260lbs and I tried with my fries who is about 180 and also with my 16yr old daughter who is about 150lbs and would not plane with either of them.. it did however plane with my 9 yr old who is about 90lbs but he had to lean up in the bow to get her up on plane.

I really think the bow that happens in the back half of the floor is what’s preventing this boat from planing. I have a thought that maybe some plywood or aluminum piping spanned across the floor of boat from starboard to port wedged under the pontoons would force the floor down an prevent it from bowing up.. I know this is not an ideal fix but I figure it may not hurt to try it.

[TmMorris]

Morning.

With pressures checked then typically you'd start assuming an issue with the engine, that it wasn't producing peak power.

So long as it doesn't damage the boat there is certainly no harm in fitting a board but I would be very keen to find a couple of other owners of the same boat to ask them if the floor deflects like yours on its way up onto the plane. If it does then this suggests a simple power issue and if it doesn't then it suggests the least likely outcome which is that your boat has been made differently to the others.

A SIB the size of yours should be able to get in the plane 2 up with a 6 in good conditions and work well with a 10 and my first thought would be to look at the engine. It's brand new and from a rather good manufacturer so you just wouldn't expect any issues but it's not impossible.

It's definitely the right length? Has the right prop? Then if other owners of the same boat tell you that the Hull bulge is normal before getting on the pane the suggestion to me would be that the motor isn't producing 10hp? Short of something simple like the launch wheels being left down.

[Limecc]

Originally Posted by BCRyan

Thanks for all the brainstorming you have all been doing to help me out here I have a little bit of an update but still problem is not solved.
Finally had a chance to try the boat out again this weekend, I ended up trying some Bennett trim tabs because I was able to get ahold of them for very cheap and figured why not give them a try.. well sure did help me get on plane a whole lot quicker with just me in the boat but did not help at all with another person with me.. I have yet to try a different prop because I could not get ahold of one before my trip to the lake, I will try that when I get back there at the end of July.

Air pressure is confirmed good. Two different gauges same reading .. 11.2psi in floor and 3.4psi in tubes.. I even tried to over inflate by a full psi to see if it helped and no difference… and psi was taken while in the water


I have tried putting the passenger in multiple spots in the boat with no luck. I actually find that it pushes more water with the bow when I have someone right up on the bow.. .

As for weight in boat I’m about 260lbs and I tried with my fries who is about 180 and also with my 16yr old daughter who is about 150lbs and would not plane with either of them.. it did however plane with my 9 yr old who is about 90lbs but he had to lean up in the bow to get her up on plane.

I really think the bow that happens in the back half of the floor is what’s preventing this boat from planing. I have a thought that maybe some plywood or aluminum piping spanned across the floor of boat from starboard to port wedged under the pontoons would force the floor down an prevent it from bowing up.. I know this is not an ideal fix but I figure it may not hurt to try it.

Not unexpected. I don't understand your resistance to buying a lower pitch prop, and want to waste time and money to modify the boat and fit trim tabs despite the good advice you got. You think you've got 9.8hp but without the right prop it might only be developing 6hp at the rpm it is able to reach. Already over-propped when solo.

[Talamex350]

Hello, I'm interested to know how the problem ended, was there a solution? I first had a 3m with 40kg, now a 3.5m with 46kg boat. the 3.5m runs better with the same engine. Best regards

[lightning]

lt's 3 1/2 years ago when the O/P posted and he hasn't been active on the forum since 2022, so we'll probably never know sadly.

[Fenlander]

>>>first had a 3m with 40kg, now a 3.5m with 46kg boat. the 3.5m runs better with the same engine

Despite going against simple logic many folks have found this over the years.