2320 Trim tab upgrade

[Bodick93]

Last weekend I upgraded my Lenco "Edge mount" trim tab blades as delivered from Parker. I went from 12*12s (which start at 12" wide and taper to 10") to 18*12s (which start at 18" wide and taper to 16").




The geometry of the tabs in relation to the actuator is identical. Same hardware, didn't have to touch the actuators. Also, Lenco ships the same model actuator with the 12*12s and 18*12s, so overstressing the actuator wasn't a concern.
Unfortunately (maybe) the only hole that was common to the original blades was the upper center hole (pointing to it). This does allow you to "install" the large blades and mark the holes. I attached them through that hole and the actuators, got them perfectly aligned across the bottom, and then taped the heck out of them (to the hull across the top of the blades) prior to disconnecting from the actuator. At that point all the holes could be drilled perfectly.



I used patience and West Marine "anti-bond 2015" to remove the old blade and sealant. Debond would have been my first choice, but I overlooked the purchase and needed it then...West Marine got me for 15 extra bucks on the 5200, and 20 extra on the antibond. I also grabbed a razor sharp steel putty knife and a bunch of plastic ones from Lowe's. I got the tiniest initial groove under the tabs with braid then applied the antibond and waited 10-15 minutes and got the sharpened metal putty knife in there. Once that gap developed, I went with plastic (they are going to break but are less than a buck) and waited 10-15 minutes between wedge increases (tapping farther in). Spray and wait, then tap wedges a little. Repeat. I had them off in an hour or so with the tiniest of scrapes on the gel coat, and all under the new tab install area..for a better grab with the sealant, so that's cool. I was amazed at how well the antibond worked, and IMO 5200 is THE sealant to use for this application. After seeing how well antibond slowly dissolved it, my opinion is unchanged.



Once they came off,

I cleaned up the rest of the sealant with more antibond and drilled the old holes larger to clean (EXCEPT FOR THE TOP CENTER ONE!). Once cleaned with soap and water, then acetone and dried, I used thickened West Systems to plug the old holes and taped them over.
I reused the zincs, which required a hole to be drilled in the new tabs.
Once the epoxy was fully cured, I applied a liberal coat of 5200 FC and the new tabs installed perfectly.

Things I screwed up:
Didn't buy a new drill bit for drilling through the stainless for the anode installation.
Didn't measure and buy a new anode ahead of time...had to use the old ones.
Didn't buy new screws ahead of time- you can't get them just anywhere..and you want quality stuff.
Didn't buy Debond ahead of time.
Didn't buy Fast cure 5200 ahead of time.
By "ahead of time," I mean the same time I ordered the larger blades. I was then at the mercy of the market, availability, and West Marine markup.
Didn't "frame" the new tabs with painter's tape when I installed the screws and cleaned up the 5200. Cleanup is easy enough, just messy.

Initial results were great, BUT I couldn't play around like I wanted because I had a boat full of people. When I applied tabs, the boat moved for a change.
I am going to the CB for Father's day and will report back after a full day of fishing and playing.
Great project, all in was about $400.00. I expect to get 100 bucks for the used blades, as they are hot items on ebay.



No projects for a while. I'm $600 in counting the new seat/ base in the the other thread.

 

[warthog5]

For you and anyone else.... There is / was a kit and could be built easy enough. It's a "Spill Plate Kit". It consits of pieces of the same material that fasten to that lip on each side. Think of a wing on a Outlaw Sprint Car. They hold and Funnel the air..... But in this case the Water on the blade. Without them Water just spills off to the side... With them it is increasing the blades efficiency and in effect acting like a larger blade / tab.

 

[A-K]

Solid upgrade on a 2320. 12x18s are generous tab for that boat.

On a 2320 I would NOT recommend Bennett 12x18 “drop fins”. They bite hard!

While on step it would make the violently lunge. Very unstable.

 

[Bodick93]

For you and anyone else.... There is / was a kit and could be built easy enough. It's a "Spill Plate Kit". It consits of pieces of the same material that fasten to that lip on each side. Think of a wing on a Outlaw Sprint Car. They hold and Funnel the air..... But in this case the Water on the blade. Without them Water just spills off to the side... With them it is increasing the blades efficiency and in effect acting like a larger blade / tab.

I thought about it, and like it. Had Bennet sport tabs on my bay boat and they had plenty of working surface.
Then once you remove the blades for modification (the stainless is NO JOKE to drill), most of the work is done already. The thing that sent me in this direction was the overlap in geometry and actuators between the 12s and 18s.
One thing I can't figure out is why the blades taper inwards at the ends.
These tabs are still 3-4 inches inside the engine bracket.

 

[Bodick93]

After a full day and probably 30 miles (it was not rough yesterday), this is a great mod and I wish like hail I had done it before I installed the Permatrim.
The way I understand stern lifting props work, the props may be in opposition to the way the permatrim works anyway.

I was able to trim the engine up 30% yesterday with 2 bars down on each tab. I was running 4200 RpM, motor sounded great, steering was neutral and was running 33 MpH and getting 2.4 mpg. 4 adults and fishing load, minus a full livewell, and only half a tank of fuel. Damn good numbers for me, and I attribute it to being able to trim out the motor and not bury tabs.
Oddly enough, the little spray the permatrim always sent up is gone.

 

[Bodick93]

Alright, so 1.5 months in, and I am 100% sold.
I took these pics a few days ago. Since the tabs are big enough not to dig in now and cause a bunch of drag, I was able to put them down a few bars to level the boat, run 32mph @ 4200 and get 2.6 mpg. I am able to trim the motor up and lighten the steering since the tabs works. Wife and 2 adult kids on board, full cooler, nothing in livewell or fishbox.
The Yamaguage refresh rate caused photo problems.