Armstrong bracket repower- twins to single

[outlawgunner]

Originally Posted by flyingfrizzle

Cant help but notice the first Pic shows the boats from Atlantic Beach, N.C. Is that where the previous owner lived or are you from down that way? Im about 45 mins away why I ask.


Any how that is defiantly not an Armstrong. Armstrong makes mainly if not only Aluminum brackets. They are mostly powder coated white but over aluminum. Yours looks to be a painted fiberglass bracket. Similar to an Hermco but not a Hermco but very similar construction to one. I would take a stright edge and see where the AV plate is going to fall in relation to the hull bottom on that bracket to figure if you need the 5" extension or not. You will want the AV plate at least 2"-3" above the hull bottom. Im guessing from the Pic you will probably be short with a 25" single but check it to see. If the AV plate falls over/higher than 3 1/2" - 4" above the stright edge you could get a lot of prop slip and have blow out in turns. If you cant get the 25" low enough in the water an extension or 30" outboard should work fine once you glass in at least the lower 4 mounting holes. I would go ahead and do all 8 if you don't plan on doing twins ever again so it seals it up.


One other thing I noticed on the first pic, the transom must have a slight crown in it outwards. I have had the same thing happen to me before in the past when redoing an transom. The weight bows it out slightly and makes you have to fill in the two outer edges of the swim platform with sealer. Not an issue or anything just an observation.

My family has a place on Atlantic Beach, stays on a lift in the canals.

Yes i believe a 25 is just not going to be quite enough, i was already looking into the idea of an extension bc that would be the easiest solution. I woulld have all the old bolt holes filled in for sure. the old motors should be off in a week or so then ill be able to figure out more on this bracket bc im almost positive that some parts of it are aluminum.

[outlawgunner]

I also thought about this as well.

[flyingfrizzle]

Originally Posted by outlawgunner

My family has a place on Atlantic Beach, stays on a lift in the canals.

Yes i believe a 25 is just not going to be quite enough, i was already looking into the idea of an extension bc that would be the easiest solution. I woulld have all the old bolt holes filled in for sure. the old motors should be off in a week or so then ill be able to figure out more on this bracket bc im almost positive that some parts of it are aluminum.

I will have to keep an eye out for the bote when Im down that way. Looks like it is a sweet hull from the limited view.


I would have a hard time thinking there is any aluminum in that bracket but I could be wrong. The aluminum vs Fiberglass ones both have different build styles and that one is defiantly built like and fiberglass. I would want a fiberglass over an aluminum anyhow and that is coming from someone that builds and welds aluminum parts. There are pros and cons up here vs the two on other threads. It wouldn't be to bad to cut down the mounting ear or notching it like mentioned. I have seen that done with success and I have even cut a few inches off of the ear on a twin dusky fiberglass bracket myself to make it work with a single 25"leg. But a simple bolt on extension would be the easiest route plus it would keep the power head further out of the water also. You will like the way the boat rides better with the lighter single for sure though.

[outlawgunner]

Full pic

[outlawgunner]

It doesn’t look like any aluminum bracket I have looked up either and looks damn close to a hermco. Making modifications would be much easier with a fiberglass bracket but simplest, easiest, and probably smartest would be the extension.

[jtharmo]

I thought it looked like a Potter/Hermco too. This is Bushwacker's photo when Don (Hermco) installed his bracket. His Seafari is in my yard now. It is a single on a 20' but the platform, tub and engine plate all look like they come together the same. The ladder looks the same also. Other than a sticker, I didn't notice any permanent marking/ID.