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Has anybody out there ever mounted so "self adjustable" trim tabs on their Montauk 150?

I'm thinking of installing a pair of Nauticus SX9510-40 in the hopes to get better out of the hole performance and get on to plane better with a full boat load (5/6 people). Nauticus said they have helped many customers put them on whaler boats over the years with much success. I believe they talk about the 17' and up models. You need 10" of height clearance from the bottom of the boat up where the actuator mounts and with my swim ladder that means it would be mounted just to the right of the ladder. i.e. close to center of the boat right next to the 60 HP where the different rise step is.
I don't want to buy these tabs and put mounting holes in my transom before I know it has been tried out on a Montauk 150.

Before somebody refers me to the 2009 and 2010 threads about why and why not to use these Smart tabs let me tell you I did read all of it but my concern is where to place them on my 15 ft. hull as I cannot do it on the outside of my transom due to where my factory mounted swim-ladder sits hence I need to know if somebody installed a set on a 150 Montauk hull.

I know it will help with porpoising and getting onto plane with less passenger shifting around.

Please show some transom pictures with mounted Smart Tabs.

E-J

[Moderator - edited text to change to model names. We do not use "15' hulls" as a descriptor since it is too vague.]

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Asking a Montauk 150 with a Mercury 60 hp motor to plane quickly with 5-6 people is quite silly. It is not about tabs or fins. It is about horsepower and torque.

The 150 Montauk has a dry weight of 950 lbs. , this is the same weight of a classic Montauk 17). The maximum rated horsepower for this boat is only 60.

My classic Montauk was a dog to plane with 5 people and I had a properly rigged and propped 2 stroke 90hp motor.

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OK Phil you have a point (although she's a dog I've gotten her up to plane with 980 lbs of people plus my standard 100lbs of gear/drinks/food) I should have left the 5/6 people out of my comment.
Let's say just 4 people which is what we normally cruise as with either my 2 adult sons or another couple.
Even by myself I still think she's a dog and doesn't jump out of the water like a boat that size should. This is with the standard "stiletto" SS prop that comes with the Merc 60, which with trimming I can get to 58/5900 rpm and running @ 29.3 knts. but she porpoises at that speed.
I'm just wondering if anybody did the smart tabs on a 150 Montauk or 150 Sport and where they placed them on the transom as it should give me better performance/handling.

[Moderator edit - Removed "15" hull" reference, please stop be generic and cite model names.]

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What style of swim ladder do you have? Can you add a pic to your page?

John K.

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Sure, Smart tabs can help. I have read reports from whaler owners who installed them and were pleased.

I would look at shifting weight forward to address porpoising. You are too light in the bow, heavy in the stern.

I would also look at the engine rigging. It may be your motor is too low. Whaler tends to be conservative on mounting height.

After the above, if you still want to add tabs, go for it.

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I know my Dauntless 15 has a different hull configuration than you are questioning, but with same approx length, a dry weight of 850 lbs., and a 60 hp 2 stroke, my Dauntless jumps on plane in less than 4 seconds with 4 adults and gear.

I'm running a 12" x 11 pitch stainless Stiletto prop, cavitation plate is 1 1/2" above the keel line and have a Dole Fin installed. WOT GPS speed is just under 34mph at 5100 rpm. However, even with the added lift of the low pitch prop, and the fin, the boat is prone to porpoise with only two aboard in the helm seat. I normally run with the motor trimmed in most of the way.

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OK...I have a dumb question, as usual. :)

Where do you people put 5-6 people on a 15' boat? With only 60 HP? I know your boat is rated to carry a bunch of people, that is not the question. 1080 lbs of people and gear, on a 15' boat? Even 4 adult people on a 15' boat with any kind of gear at all won't happen with me as a captain.

You don't need trim tabs, you need a pontoon boat. JMHO.

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Actually, 4 adults fit just fine in my 15' Dauntless. Folks have been carrying 4 adults for decades in 14 or 15 runabouts with 35 or 40 horsepower outboards. Just pick your days, watch the weather, and learn how to pilot responsibly.

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You are right Gary 4 people is no problem on my Montauk 150, and even though I take this boat on Lake Michigan (weather permitting) it is more designed for inland lakes. Also the 6 person plate rated at 960 is a little light as I per the capacity plate couldn't have 4 of me on board. Hell as a captain I won't take an 18" Outrage 15 miles off shore to go fishing with only 2 or three people.
I use an old 14' Achilles commercial "dive" boat with 25HP 2S when I want to move 8 people no matter how heavy they are and if some friend wants to go salmon fishing out 20 miles I take the cabin cruiser and take every-bodies family too.

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John sorry for the late response but hopefully these pictures will show the type of swim-ladder I have on my Montauk 150 I had to do some down & up loading.

http://wilsonbrinker.com/ej/2008Monta...8-2014.jpg
http://wilsonbrinker.com/ej/2008Monta...8-2014.jpg

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Ah, I see the problem, you can't clearance the metal ladder rung to get the Smart Tab piston to fit under it. What about using some wooden blocks/metal brackets to stand the ladder off of the stern?

John K.

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John,
Yea I probably have to but the Admiral won't let me as she thinks the boat runs fine. I'll make a decision this weekend after I take a loom what my friend did and measure his setup.

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E-J,

Do you know what prop you are running. Maybe a lower pitch/ larger diameter prop would help with the porpoising. It looks Luke your motot is mounted in the center holes, so maybe another hole up might help with the top end. Others with more prop tuning skills might chime in on this, but swapping out my Old aluminum Merc prop for the much larger diameter stainless Stiletto made a world of difference.

Just a thought.....

BTW, I'm interested in how this turns ou since the 60 Merc Big Foot is on my short list as possible repower for my 15 Dauntless.

Gary

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If the ladder is in the way, just move it up.

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Looks to me like the ladder might conflict with the trim tab when it's in the dropped down position.

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If you decide to go with the trim tabs and the ladder becomes an engineering issue, I installed a Platismo safety ladder would attach to the two uprights for the walk through of you stainless rails. Removable when not in use.

Garris

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That is a good point Garris but as mentioned B-4 a tough sales job. This is our "shallow" water inland lake cruising boat and the Admiral & I have to be able to get out of the water easy as we are getting older.
Gary as I think I mentioned B-4 my WOT speed with perfect trim is very acceptable with my Vengeance 48-17314 (13-3/8"x 14) all Stainless prop at a speed of 29.3 knots (33.7 mph) with 450 lbs extra weight on board. This is with the bottom of my anti-cavity plate equal to the bottom of my transom (the Montauk is rounded not "V"ed so I can't call it a keel). With a lighter load (myself, 1 full 6.5 gallon tank, and no gear) I've been able to clock her at 34.6 mph and just not porpoise, not a safe speed for this boat as your trim must be precise and the water like glass. Just add an other person and/or the gear and this 950lbs boat rides much better at a very acceptable top speed..
I'm not looking as much for speed as I'm looking for out of the hole speed (without getting a 2S 70 or 90 HP).
Also again smart trim tabs $110 + 1 hour install; or new SS prop $295 (cheap) with 1/2 hr install; or raise engine 1 hole (#2 from top) cost $0 and 2 hrs or more of work.
Prop install advantage would not be known to layman's eye as all looks the same but it has a high initial cost, raising engine trying to find a support that can handle my engine weight on a come-a-long/winch not easy, advantage low cost and again not known to layman's eye as all looks the same but also not known if it helps the hole shot. I currently trim all the way in to keep the boat from porpoising so for a minuscule higher top speed this a lot of work.
For those two reasons I like to do the in-expensive smart tabs that will work. With the dis-advantage of drilling holes in transom and it will get noticed, but the performance will be noticeably better and therefore an easier sale for the expence.
Garris do you have a link for the ladder?

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www.platismo.com is for the manufacturer. Plug in "platismo ladder" and you will get a lot of local sellers (it is a company in France which produces). I have the one that you can deploy from outside the boat and it stays in a sack on the gunnel between my rail walk through uprights.

Garris

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Try a swim platform or install a portable ladder.

Martin Marine makes top quality products specifically for Boston Whaler boats. Contact Ray and ask what he can offer for a Montauk 150. http://www.martinmarinedesign.comdesign.com

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Thanks Garris and Phil I'll check it out.

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Hello EJO and excellent looking Montauk 150. I have been following your thread and will offer some opinions, exhaust all avenues to correct your hulls "getting on plane" issue before drilling into your transom.

I have hydraulic Bennett trim tabs on my Dauntless 15 and have as of yet to actually deploy them (and I've owned my Whaler since mid-2008). The previous owner had them installed and what a mess I discovered. I am aware that you are considering a "self-adjusting" type but, how sensitive are they when slapping against mild to choppy surf? Can the attitude of the hull be suddenly affected should a tab change or loose it's height setting? As is my case, a 15 foot hull length with barely over 5 feet of beam is extremely and uncomfortably sensitive to trim tab input.

What actually concerns me is the lack of any strong substrate within the transom area where your trim tabs need to affix to. Soon after purchasing my Dauntless I discovered numerous loose fasteners at the trim tab bracket to transom plate along with inadequate sealant. Small amount of moisture wicked for days from the various fastener locations (for both Port and Starboard) when I dismounted the tabs. Review my project album for the repair method I used due to the lack of any wood or ample fiberglass thickness in those immediate areas. It was a mission to due it properly.

My situation is a bit different since my Dauntless is slightly over-powered, there's sufficient power for the "hole-shot" but a bit more weight as well. I typically boat with 4 occupants (my wife and our 2 adult kids and soon my daughters boy friend) that will make 5 adults and he's a big guy. My Yamaha 2 stroke is mounted all the way up, cavitation plate is about 1-1/4 to 1-3/8 inch above our so-called keel. From my personal experience, my set-up is great but a jack plate could make it more interesting.

Originally I had a Solas (early model) Saturn S.S. 3-Blade 13-1/4" Dia. x 17P prop with round ears. Some sites reference these props as bow-lifting and it certainly is/was. When attempting plane it would bury the stern and point the bow to the clouds, I would have to consciously feather the throttle until the stern would rise. And yes, the drive or lower unit would be tucked all in rather no positive trim. Now I am using a new to me Power Tech S.S. 3-Blade 13" X 17P "Semi-Cleaver" prop configured for the Yamaha 90 2 stroke. This particular "Semi-Cleaver" prop is modeled off of a Yamaha OEM prop, "Semi-Cleaver" props are considered a stern-lifting prop and this one certainly is. With the 4 of us I can get on plane immediately when coming out of the hole with minimal stern drag. Staying on plane at lesser rpm has also been an added benefit that the Solas struggled with.

I replaced the OEM fiberglass Pate 15 gallon fuel tank with a Moeller plastic 18 gal which resides within my helm seat housing. I feel this tank location offers a slightly better weight distribution unlike smaller tanks at the stern regardless of their capacities. My single battery is located within the center console as well.

How is your weight distribution??? Fuel and battery location???

You can forgo a hoist or pulley system to raise your outboard EJO, if you have a healthy floor jack and you are comfortable with some wood work you can construct an appropriate bracing or cradle for your lower unit that will possibly supports either the gear case, cavitation plate or both and with 1 or 2 friends carefully raise your outboard up to a new position. If you are aware of a local prop shop they sometimes will due a "lend-lease" plan for you to test a propeller before purchasing. Just supply them with spec's of your whaler to use as a guide during a selection.

Porpoising is an interesting phenominum, My Dauntless is seriously "positive trim" sensative. Fortunately I have a Yamaha digital tach with a trim bar display and over time and use I have finally found my outboards sweet spot, 3 bars up on the display and all the throttle she wants until the moderate chop influences the ride then drop it 1 bar down.

I have shared a lenghty post with you in the hopes that you consider other factors and/or solutions to your "getting on plane" dilemma before embarking on drilling into your transom. If I had to re-do my tabs sometime in the future I would remove them completely.

If raising your outboard remember to re-seal the transom fasteners/bolts for the outboard with an appropriate sealant such as 3M's 4200. I consider the 5200 a bit to aggressive for this application but, that's my opinion.

Best of luck with your solution and "Happy Boating"...

Angel M.

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Thank you Angel and see my responses below. I loved your detailed reply and thank you for taking the time to respond in such detail, you made the scale tip to what we both think is the right side.


My concern too hence the original question, I don't want to repair something after putting holes in and taking it off because of no performance difference.


My new 150 is slightly wider and heavier, but you are probably right


My concern too I don't see any substrate where I should be mounting. I have used the same fasteners you used for your tabs to hold down a large cooler we use for storage and a seat, can't be beat and the SS screws work fine with the brass.


I love to have a little more power like a 70HP E-tec 2/S, but that's not going to happen in the near future as long as my 60HP Bigfoot purrs like a kitten as it does. It sounds like you run with the same type weight as I do quite often.


That is my current problem with a larger load, hence I have to move a person to the bow and back to achieve quicker plane.
As I have given up on re-laying-out my transom to accommodate trim-tabs I'm now looking at going 4-bladed prop and OB re-mount


I still have the 2 single 6-1/2 gallon tanks under the RPS, battery in CC, also an quick start emergency portable battery, 11 lbs Danforth and 12 lbs river(3 blade mushroom) with 15ft of 3/8 chane and 200+ ft of rode in bow locker, than I also have a large 128qt cooler in front of the OB (where live-well would sit) as an extra seat and filled with PFD's, fenders, lines, etc. and of course the small cooler with food and drinks in front of the CC, All this adds extra weight and convenience.


Thank you for that [b]great tip[/] as that I can do pretty easy (might do that this weekend) I'll mount one hole higher (which I think will be slightly over 1" above the "keel").


I'm in Michigan where they only have 4 months or so to make money on boating so there isn't a service like that here at least not in my area. I tried it with Michigan Wheel which manufacturers close by here in Grand Rapids for my twin engine 32' cruiser and believe you me those brass props were a lot more expensive than a small OB prop and therefore had a much larger margin in them if they would sell. Here it is buy, try, and re-sell at a loss, if it didn't work. Theory is theory, practice makes perfect.


I thank you for that and yes I try the engine up on the transom and a 4-bladed prop, before drilling, mounting, getting another ladder, etc.


I agree. It si above the waterline so I shall use 4200 or poly-sulfide bedding compound.
We'll raise the engine first and then try the 4 bladed prop in the near future if I get a chance to do so B-4 the water gets hard here up North and post results.

Thanks again Angel and "Happy Boating" to you too...

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To raise the motor, you don't need a jack. You can use the trailer and trailer jack. Even though the 60 hp is light, a second set of hands is necessary.

Block the wheels.
Lower the tongue of the trailer all the way down with the jack.
Lower motor till vertical.
Block motor skeg on ground.
Loosen bottom bolts (in slots)
Remove top bolts (Have buddy hold motor still)
Raise tongue jack till holes line up
Recaulk top holes and reinsert bolts. Caulk and tighten nuts
Caulk lower bolts and nuts, tighten

DO NOT use 4200. Use a SEALANT

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Phil just read your post this morning. I tried what you said yesterday as you can't put a floor jack under the engine. My original BW Karavan trailer is not high enough to put the engine all the way trimmed in without the skeg hitting the ground even with the tongue lowered all the way.
I did built a double "U" out of 2"x 4" to support under the skeg, straight up to the cav. plate and support also each side on the front of the cav. plate. Lowered the tongue, and used the engine trim to put motor on the ground. Loosened the nuts asked one of my two adult sons to help me keeping the engine balanced but was unsuccessful in convincing them to come home with me(20 minute drive), even after I bought Sunday breakfast for the four of us.
Needless to say it didn't happen, the motor is still mounted center holes (2 from the top or 2 from the bottom however you want to look at it) with the cavity plate even with the keel.
I'm ready now and if I have help can do it in 1/2 hour or less.

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Hello EJO, it was my pleasure to input. I didn't consider the ride height of your trailer v.s. ground clearance to the skeg. Glad to hear Phils trailer suggestion will do the trick for your outboard height adjustment.

I'm sorry to hear that you do not have the convenience of a local prop shop that would be willing to accomodate a lend-lease option for testing. EJO keep this in mind, as you test heights a stainless prop will be needed as it nears the surface. Aluminum props typically do not fair well nor offer the needed performance when turning near the surface either by a raised outboard or by a positive trim setting.

I too considered a 4-blade prop when working through my own "getting on plane" dilemma. I received some "pros and cons" from members here on W/C when I asked for input. If you haven't yet ask for some prop advise, the topic has been discussed at significant lengths so search the site for info then post a thread. 4-Blade props can be a bit tricky and costly to select and in your case where you can't pre-test before purchasing...definitely research. Don't knock a 3-blade prop just yet EJO, I was very surprise with the Power Tech "semi-cleavers" performance.

I'm not quite sure why Phil advised against 3M's 4200, the bulk of boat riggers here in the Miami and FL. Keyes area use 5200 over the less aggressive 4200 for sealing outboard transom bolts. I am aware they are considered to be more adhesive than sealant but from my experience where applicable, the 4200 has remained flexible with little to no yellowing from exposure and with excellent water seal. In the event I should ever need to remove the 4200 I came across a product in aerosol spray form which aids in breaking down the adhesion binders in 3M's and other marine type adhesive sealants with makes removing it almost as simple as pealing it off like masking tape.

Well good luck with the prop selection and motor height project...post when you've had some test time with the Montauk 150...till then.

Angel M.

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Can you drive the trailer wheels up on some 2x4's ?

I have a couple of 4x4's cut on a 30º angle on one end so I can drive a trailer, quad, lawnmower, etc. up on them so I get enough ground clearance to work beneath the equipment.

Will a 2x4 give you enough clearance?

If you use this method, don't forget to block the wheels so the trailer won't move.

(Edit: changed the cut to about 30º)

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Joe I probably have to use 4x4's and keep that in mind.
Thank you.

I'll do the raise OB first with my 3-bladed SS Vengeance prop and report back.
Ran alone for timing and speed to record so I can know the difference when lifting the engine up.
She took a good 10 sec. B-4 leveling off but she did get up to 34.7 mph on GPS running 6,000 after fine trimming.