stabilizers

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LuredAway

Veteran Member
Joined
Mar 20, 2017
Messages
33
Location
USA
Vessel Name
Sweet Freedom
Vessel Make
Monk 36
In my never ending search to find a boat I ran across a 2005 Mainship 34 with stabilizers. I really don't know too much about stabilizer, I do understand the concept. I am just surprised to see them on a boat of this size.
My questions are:
1. Are they a significant maintenance issue
2. Are there negatives to having them
3. Just how much do them impact fuel consumption and speed

Thanks

Tony
 
1. All machinery requires maintenance. Stabs are not difficult or time consuming. Expense is relative.
2. Cost. In this case since someone else already paid for them none.
3. The wind and waves will have a bigger impact and you will be able to run in those conditions faster and more comfortably.
 
Where will you be boating? For ICW and inland cruising they are not needed and are an added expense. I'm not sure how effective they are on a 34. What brand are they?
 
2. Are there negatives to having them
3. Just how much do them impact fuel consumption and speed

Main negatives are parasitic drag and they can pick water based plants, seaweed and the like. Many owners place guards in front of them.

Don't know first hand but I have read several boaters report a drop of up to .5 knots with stabilizers and fuel economy drops under 5%.
 
The negatives of stabilisers are insignificant compared to the benefits. Unusual for a 34 to have them (active fins?) but a huge plus.
 
Where will you be boating? For ICW and inland cruising they are not needed and are an added expense. I'm not sure how effective they are on a 34. What brand are they?

Perhaps not "needed," but certainly appreciated when crossing sounds, bays or other open water when the wind's up. The difference on my boat with stabs on/off is striking.
 
Will be getting more information on the type soon, the brand is Wesmar but not sure of the type. Maybe a dumb question, do stabilizers add to draft minimums?

Our boating will be east coast FL, down to the keys and maybe Dry Tortugas. In a few years maybe up to Great Lakes
 
I owned a 34T on the west coast and used it for trips from Long Beach to Catalina island. Active hydraulic stabilizers would have definitely made that run more comfortable 80% of the time. But they are only effective if you go fast and since 12 kts is about all you can do with the single Yanmar the 0.5-1 kt lost to drag will be a killer. As it is that boat is barely "planing" at 12 kts. If you drop down to 11, it will be pushing the hump and eating a lot of power.

If the boat has twins then ok you have the power to get up to 12 or better, but I don't see how you can squeeze stabilizers into that boat with twins.

From Melbourne south to the beginning of the keys you will probably be inside and won't need stabilizers, but if you go outside which you might do to avoid the bridges south then they might be useful. Down the keys outside in the Hawk Channel you will be mostly protected as well. The only place you may really want them is going to the Dry Tortugas. In the Great Lakes, probably.

David
 
Wait, what? Active fin stabilizers only work if you go fast? Did I mis-read that?
 
Wait, what? Active fin stabilizers only work if you go fast? Did I mis-read that?

Assuming the fins added by someone who knew what they were doing:
-no they wont increase the draft or protrude beyond the side of the boat
-they should give some benefit even at 5-6kn, and be really effective above 7kn. Maybe that's fast for some people.

Wesmar fins might be OK, depends on how new they are and quality of install. Some older ones were pretty terrible.
 
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Fins work at all speeds. The computer on my stabilizers is connected to a speed sensor on the prop shaft.

I dont know how much drag there is, but suspect it will be nearly unmeasurable.

Gordon
 
Assuming the fins added by someone who knew what they were doing:
-no they wont increase the draft or protrude beyond the side of the boat
-they should give some benefit even at 5-6kn, and be really effective above 7kn. Maybe that's fast for some people.

Wesmar fins might be OK, depends on how new they are and quality of install. Some older ones were pretty terrible.
I have Wesmar fin stabilizers on my boat. They were installed (by a PO) in 2000. They still work very well.

The don't affect the draft and I'm typically doing 7-8.5kt

Richard
 
My 7 ft2 Wesmars work just fine between 6 and 10 knots. Installed at factory in 2004 and all parts are supported by Wesmar including electronics. Just had the third servicing (about every 3-4 years) done on this month's haul out
 
Glad to hear of two happy Wesmar users. I may have been too harsh!

I remember a TF member (Bohans?) who said he hated them so much that he would never again have a boat with active fins. Not sure about the specific issues, but apart from quality of install there is always the quality of maintenance as well.
 
Glad to hear of two happy Wesmar users. I may have been too harsh!

I remember a TF member (Bohans?) who said he hated them so much that he would never again have a boat with active fins. Not sure about the specific issues, but apart from quality of install there is always the quality of maintenance as well.

I'm sure there are plenty of opinions of any brand of gizmo we enjoy. Just like geologic intrepertation of Olympic Dam. Good beer talk for sure.

Two years ago we met up with a couple who were having a very difficult time with their newly installed Naiads. The "best" installer in Seattle undersized and haywire plumbed the cooling system. No fault of the product, just the install.
 
The question with after market is always install quality.
Will they snap off or knock a big hole hitting an obstruction?
 
Fins work at all speeds. The computer on my stabilizers is connected to a speed sensor on the prop shaft.

I dont know how much drag there is, but suspect it will be nearly unmeasurable.

Gordon

I tested my stabilizers in four foot ocean waves and I was not able to detect any difference in boat speed with the fins operating, or locked in the centered position. I also slowed the boat to idle speed, about four knots, and the fins were still effective, although they were deflecting at a greater angle than at faster speed. I would assume that in any given sea conditions there is a minimum speed.
 
The question with after market is always install quality.
Will they snap off or knock a big hole hitting an obstruction?

If you hit something with enough force to snap off a stabilizer fin, the fin is probably not the biggest problem you'll have that day.

As others mentioned, install is key. The brand is only part of the equation. Undersized fins won't be effective except at higher speeds. Our Solo came to us with Wesmars installed, aftermarket. The install wasn't top notch. Luckily, the basics were sound- good design/application, fine structural integrity (our hulls are designed for stabilizers, some just don't have them installed OEM, but the structure is there nonetheless) - but the details of the install were lacking- wiring not tidy, hoses not routed the best, and most importantly, seals on the stbd fin shaft installed upside down. This allowed seawater into the shaft and it corroded and galled. Bad! I was able to free it and correct the damage without significant rework, but my buyer survey missed it, along with many other items. Another story. But all fixed.

I would not be without stabilizers. And NO, YOU DO NOT HAVE TO DO 12 KTS. for them to be effective. That is patently incorrect. Ours work at 5 kts. The only time I've done 12 kts is leaving Montreal or on the East River! It's a function of the area of the fin, and integral to the design for the individual boat, not one size fits all, by any stretch!

Maintenance- I've re-sealed the shafts on 5-6 yr intervals, it's a day's job, I DIY and need a hand to re-insert the fins, although I've done it solo. The seals are COTS Parker-Hannifin hydraulic cylinder seals, Wesmar sells them for 5X $, there is also an O-ring seal, also COTS at hydraulic supply house. A fiberglass sleeve bearing, maybe req'd every other service is OEM, not cheap, tricky to R&R, a dry ice bath helps install.

Drag/performance loss- who cares? It's so minimal. The difference in on/off is literally stuff flying off shelves. If you do big water, stabilizers are a godsend. Even ICW cruising is enhanced with the difference they make in handling the wakes of those wonderful sportfish delivery jocks.

If your new-to-you boat came with stabilizers installed, thank the installing owner, they did you a huge favor!
 
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Thanks to everyone for the insight and advise. I will most likely take a trip across the state to see the boat first hand

Tony
 
Hi Brian. Just caught this thread on active stabs. I had wesmar fins on a 53ft boat. The fins worked well but i would not pay for them given my coastal boating needs. I think that is the dritical part...what use do you have for your boat. What i did not like about the active fins is the maintenence. They need to have seals replaced each 2 years or so. When i bought my previous boat the fins had not been serviced for several years. Although they worked fine the bearings were shot and they ate the shafts. All fixable as here in Aus we have one of wesmars top mechanics based on nsw central coast. I had to fly him in for 4 days while he rebuilt the whole things. So that was expensive.

Also the location of install is critical. Mine were too close to keel of the boat and this limited their effect.

Because i do not leave marina often the fins would always get fouled up with hard growth and then when you use them this cuts into the outer seals...

Anyway i think they are awesome just not for me.

My current boat is 72ft and i have never felt the need for stabilizers even when it is rough. I dont really care about a bit of rolling especially given the expense and need to haul out being determined by my fins.
 
Bohans, the issues and low use you describe could be the case for any brand active stabilizer it would seem. BTW, your DF 72 sounds interesting. Care to tell us a bit about the vessel. Thanks
 
Not a problem there is plenty of time and plenty of boats .....I enjoy the hunt
 
In my never ending search to find a boat I ran across a 2005 Mainship 34 with stabilizers. I really don't know too much about stabilizer, I do understand the concept. I am just surprised to see them on a boat of this size.
My questions are:
1. Are they a significant maintenance issue
2. Are there negatives to having them
3. Just how much do them impact fuel consumption and speed

Thanks

Tony

Tony

Nice boat as shown in the ad. As already noted, others thought so too. Once you're serious, get your financing in order and move. Good boats go quickly.
 
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I think the gyro stabilizer has a big advantage over the exposed wings. No drag, less maintenance plus the boat looks better when out of the water. [emoji16]
 
I think the gyro stabilizer has a big advantage over the exposed wings. No drag, less maintenance plus the boat looks better when out of the water. [emoji16]
Requires a generator to be running full time though. On larger boats that's normally the case. With my boat I am not usually running a generator under way.

Richard
 
Yes, your correct, that is certainly a minus. However there are 12 volt systems but I don't know much about them.

In my case when I leave the dock my gererator is running and doesn't shut down until I dock and get 110 volts. The new common rail gen set with underwater exhaust is so quiet I never hear it. I have been accused of being hard of hearing. :)
 
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