What size bennet slts.

[LandOfRath]

I have a Smokercraft Osprey 162 dlx
The boat itself weighs just under a 1000 pounds and has a 4 stroke 75 merc on the back
So light boat heavy motor. My hole shot is horrible and when running up river the porpoising
makes it almost unusable. I am not having any listing issues just need to get that front end down.

Been looking at self leveling tabs ,Leaning towards the Bennets SLT6. The website says the smaller ones work on boats up to 16 ft but that puts me on the upper end of that size. Are they enough or should I go with the SLT10s?

 

[Mc Tool]

Does your motor not have power trim ?
Also give some thought to weight distribution .
They are rated for 115hp max so Im thinkin that the weight of the motor shouldnt be an issue ....nice looking boat ,it would do me .
I have a light weight boat with a heavy ( for the boat ) motor and I have moved the fuel tank up front and am thinking of moving the battery there too . Usually porpoising is because there is not enough trim in or to much weight at the back . That boat looks a new enough design to not need anything retro fitted to get it to behave .

 

[LandOfRath]

Does your motor not have power trim ?
Also give some thought to weight distribution .
They are rated for 115hp max so Im thinkin that the weight of the motor shouldnt be an issue ....nice looking boat ,it would do me .
I have a light weight boat with a heavy ( for the boat ) motor and I have moved the fuel tank up front and am thinking of moving the battery there too . Usually porpoising is because there is not enough trim in or to much weight at the back . That boat looks a new enough design to not need anything retro fitted to get it to behave .

I had a mobile marine guy come last year and he recommended tabs, at the time I was thinking of just selling it but now I am leaning towards keeping it, The gas tank would be hard to move since its built in and there isn't really anyplace to relocate it too..

Yes the boat motor has trim but its just not doing enough..
I cant go slow speeds and get the bow down at all.. My old ski boat worked fine with a little trim adjustment. Yes the boat is rated for much bigger sized motors but the 4 stroke motors are bigger and heavier than most 2 stroke ones of larger power. but its what I got and it has almost no hours on it so.. I think the motor is almost 400 pounds. so motor and fuel equals about half the boat itself..

Its mainly just going to be for weekend fishing trips on the local rivers and lakes. and just trying to make it work for my needs without investing to much for now.. rather put money towards a new trolling motor setup.

 

[Stinnett21]

That motor should snap that boat right out of the hole. Something sounds wrong. How long have you owned the boat?

 

[flashback]

I'd go with the larger tabs since your border line with the smaller.

 

[LandOfRath]

That motor should snap that boat right out of the hole. Something sounds wrong. How long have you owned the boat?

I've had it for a couple years but have not used it much.. if I hammer the throttle it will plane out but if I cross rough water from other boats or ships it become an interesting ride. As far as I know the boat was purchased new in it's current configuration..

So my current experience with it is 5-6 trips in our local lake and about 8 hours on the Columbia river where I really got to experience to bouncing issues.

it was my friend's dad's boat that he only used on hunting trips which probably involved it being loaded up with gear.

 

[LandOfRath]

I'd go with the larger tabs since your border line with the smaller.

That's what I was thinking.. but the company has not replied..

 

[airshot]

Any pics to share ? Is the fuel tank in the rear ? My Sylvan has the 18 gallon tank in the floor on center about 3/4 of the way back and it balances very well. They do make props that are designed to give more bow lift, but for now....what is your RPM at wot ? Pics from the side showing the motor on the boat and how the angle and position of the cav plate. Unless you have all the weight in the rear, trim tabs should not be needed. Seeing you boat layout might help us make better suggestions.

 

[LandOfRath]

Any pics to share ? Is the fuel tank in the rear ? My Sylvan has the 18 gallon tank in the floor on center about 3/4 of the way back and it balances very well. They do make props that are designed to give more bow lift, but for now....what is your RPM at wot ? Pics from the side showing the motor on the boat and how the angle and position of the cav plate. Unless you have all the weight in the rear, trim tabs should not be needed. Seeing you boat layout might help us make better suggestions.

I might be able to get photos tomorrow it's parked at a house I am flipping.. yes the motor, fuel and one battery are all at the back.. 2nd battery up by my feet.
I can not remember what the rpms were but I believe they were on point..

I have gone through most of these things when I got the boat.. just now wanting to do something about it.. I am pretty sure the tabs will make a large improvement and get it back on the water.

 

[Mc Tool]

I have these two things on my boat to aid with trimming .
The transom wedges give you more trim in and the other thing is a permatrim which is made in NZ so maybe not available in USA but there are others similar . Some say ( here they come ) you dont need them but I had one on my previous boat and took it off to see what happened and I could not stop porpoising so it went back on . That boat was overpowered ( read motor was to heavy ) and it worked a treat . To be fair it didnt make much difference on this boat but it is underpowered ( needs a 70hp 2 stroke but has a 35hp 4 stroke ...which weighs about the same as a 70hp 2 stroke ) .
Your boat sounds to be suffering from to much weight at the back . Built in tank ...your right ...cant be shifted . If that were my boat I wouldnt hesitate to fit a similar cav plate extension as it will give you more lift .

 

[LandOfRath]

I have these two things on my boat to aid with trimming .
The transom wedges give you more trim in and the other thing is a permatrim which is made in NZ so maybe not available in USA but there are others similar . Some say ( here they come ) you dont need them but I had one on my previous boat and took it off to see what happened and I could not stop porpoising so it went back on . That boat was overpowered ( read motor was to heavy ) and it worked a treat . To be fair it didnt make much difference on this boat but it is underpowered ( needs a 70hp 2 stroke but has a 35hp 4 stroke ...which weighs about the same as a 70hp 2 stroke ) .
Your boat sounds to be suffering from to much weight at the back . Built in tank ...your right ...cant be shifted . If that were my boat I wouldnt hesitate to fit a similar cav plate extension as it will give you more lift .
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Yeah I have been researching all night and found multiple posts from people with similar boats having the exact same issue with the conclusion that the 4 stroke motors are just to heavy.. this is an earlier osprey so I think it weighs 960lbs so full of gas and motor is over half the weight.
The motor has a similar tail on it already and it didnt help.

The tabs are something I can easily do myself and I can always remove them or upgrade them at a later date which is why I was looking at bennett over smart tabs... small cost that might get it back on the water and let me enjoy it sooner than later. I have spent a lot of time trying to solve the issue over the past couple years and I just want to use the boat. As I said I had a professional marine mechanic go over it all and his conclusion was tabs where a good option.

 

[airshot]

How much fuel is being carried at the back ? A six gallon tank us not a big deal, but 12 or more gallons does become a big deal !

 

[LandOfRath]

How much fuel is being carried at the back ? A six gallon tank us not a big deal, but 12 or more gallons does become a big deal !

I think it's a 16 or 20 but I'm not really sure