190 Montauk Trim Tabs: Five Questions

[StillAmSamIAm]

Only for readers who have installed trim tabs on a 190 MONTAUK:

Q1: were the trim tabs electric or hydraulic type?

Q2: what size trim tabs were installed?

Q3: where on the transom were the trim tabs installed? Please give exact measurements and details.

Q4: are there any tips for the installation?

Q5: are there any things you wish you had done differently during the installation?

BACKSTORY
I recently purchased a 2018 Montauk 190. I may add trim tabs to improve handling and ride quality in windy conditions with beam seas.

[jimh]

Q6: have you read the REFERENCE article on trim tab installation on Unibond hulls?

Cf.: Trim Tab Installation
https://continuouswave.com/whaler/refer ... mTabs.html

[Jefecinco]

The 190 Montauk is a modified V design with modest deadrise. As a former owner I believe tabs are not needed.

[jimh]

I recently purchased a 2018 Montauk 190. I may add trim tabs to improve handling and ride quality in windy conditions with beam seas.

Regarding the behavior of the hull of a 19-footer in beam seas, I don't think trim tabs are going to have enormous influence. During really windy conditions, the force of a large wave hitting the hull from abeam will be very much stronger than the force that one trim tab on the lee side of the boat can exert on the hull.

Trim tabs are effective in creating a level side-to-side trim on the boat when the hull is on plane and there is significant wind from forward of amidships but not directly ahead. Typically a Boston Whaler hull in those wind conditions will tend to lean into the wind. On a relatively small boat with a moderate V-hull, the lean can be compensated for by moving some weight athwartships. The weight of one adult person aboard the boat being moved a few feet laterally will often compensate for the hull's lean to the windward direction. On the other hand, if weight distribution is creating the uneven side-to-side trim, then you could correct for that by using trim tabs. But in doing so you will be creating added drag on the hull, and the added drag will reduce speed and likely decrease fuel economy.

Probably the most effective use of trim tabs is to push down the bow of the hull during acceleration onto plane from slower speed, and particularly so if the hull form and weight distribution exhibit a tendency for too much bow rise in this situation. But generally with Boston Whaler boats, appropriate engine weight, and proper weight distribution, excessive bow rise during transition to plane will not be a problem.

While having trim tabs can be useful at certain times, at other times they are just another control to remember to adjust properly when conditions change. For example, if the trim tabs are set to produced a bow down force when making headway, if the boat makes sternway the tabs will tend to create downward force on the stern.

Also, running fast and on plane with large beam seas is not a particularly comfortable or safe mode of operation. Altering course to put large seas on the stern quarter and then then jogging alternately upwind and downwind is perhaps a better strategy.

[fno]

While I agree with both JImH and Butch on this subject plus the fact that you think they will help with running in beam seas (they won't) I will attempt to answer your questions.

Q1: were the trim tabs electric or hydraulic type?

A1: Electric (Bennet) Electric is instantaneous change. Hydraulics have a slight lag.

Q2: what size trim tabs were installed?

A2: 9" x 10"

A3: where on the transom were the trim tabs installed? Please give exact measurements and details.

A3: At the bottom but up a 1/4" Install them where the mfg. says to. Exact measurements and details? Someone can come and do this for you....

Q4: are there any tips for the installation?

A4: Don't use the supplied screws to hold the tabs on the transom. Chinese crap. Broke two. Buy good 316 SS screws from McMaster.

Q5: are there any things you wish you had done differently during the installation?

A5: I wish I had ought the McMaster screws up front. Drill one size larger than recommended and use 5200 to seal the screws. I had to relocate my tabs slightly to not hit the broken screws.

[fno]

I forgot to mention, you are new to this site. It is a wealth of good and great information, but you have to put some time and effort into finding what you need. Maybe you should look at the parts drawings available on Boston Whalers website for this model boat. They may tell you where to put the tabs but at the least they will show you. One thing this site is not, a free source of infinite guidance on the basics of boat ownership, maintenance, and the pain, suffering and cost of the pleasure of owning a Boston Whaler.