Transom height for SC20 Master Angler

[Chaser]

Hello all,

I recently acquired a 1978 SeaCraft Master Angler 20. I'm excited to get it back on the water. The boat has been sitting out in the weather for about ten years, so its in kinda rough shape. I plan to do a modest restoration including fixing the decks where the core is rotten and soft, topside paint, and re-power. I have a rigging and boat shop so I'm doing all the work myself, except for the outboard.

When I got the boat, it had a 1985 Evinrude 235hp outboard on it. It was supposedly re-built some time back and in OK shape. Well, turns out it was shot it had been overheated and is basically scrap. I'm going to put a re-built Mariner 175 on it instead, being built at a local shop.

The boat currently has a 20" transom. The motor can be built with either 20" or 25" transom height, its my call I just have to let the mechanic know. The transom is actually in very good shape, with no rot or soft spots at all, so it doesn't need repair. But since the boat needs a bunch of other fiberglass work I'm thinking about raising the transom up to get the powerhead further away from the water.

The waterline on the boat has been raised I think as a result of the weight of the large outboard. It also has splash plates and some other devices to keep from being swamped. Obviously it sat stern down and had problems getting swamped. Does anyone have a recommendation as to whether the 20" stern height is too low? I've searched around the forum a bit and haven't found exactly the answer I'm looking for.

I'm spending a bunch of time and money to get the boat in good shape. Its a great boat and from everything I've read here I think I'll be really happy with it. I don't want to go through all this work only to find out I really should have raised the transom when I had the chance.

Whats the advice?

[htillman]

I recommend raising the transom while you are getting the boat in shape. If you dont, you will probably wish you had later down the road.

[McGillicuddy]

I don't think there is a sane person on this forum that wouldn't raise their transom from 20" to 25"given the skills, space, and materials. Not sure what year your mariner is but if its in the 360# class like mariner magnum, etc. you'll have a great ride when your done

[bly]

Originally Posted by Chaser

Hello all,

I recently acquired a 1978 SeaCraft Master Angler 20. I'm excited to get it back on the water. The boat has been sitting out in the weather for about ten years, so its in kinda rough shape. I plan to do a modest restoration including fixing the decks where the core is rotten and soft, topside paint, and re-power. I have a rigging and boat shop so I'm doing all the work myself, except for the outboard.

When I got the boat,

it had a 1985 Evinrude 235hp outboard??????? on it. You think the transom is in good shape after this was hanging on it?


It was supposedly re-built some time back and in OK shape. Well, turns out it was shot it had been overheated and is basically scrap. I'm going to put a re-built Mariner 175 on it instead, being built at a local shop.

The boat currently has a 20" transom. The motor can be built with either 20" or 25" transom height, its my call I just have to let the mechanic know. The transom is actually in very good shape, with no rot or soft spots at all, so it doesn't need repair. But since the boat needs a bunch of other fiberglass work I'm thinking about raising the transom up to get the powerhead further away from the water.

{{{{{{{{The waterline on the boat has been raised I think as a result of the weight of the large outboard. It also has splash plates and some other devices to keep from being swamped. }}}}}}}}}}}
{{{ Obviously it sat stern down and had problems getting swamped.}}}}} }}}}}}}}}}}}}}}}}}


Does anyone have a recommendation as to whether the 20" stern height is too low? I've searched around the forum a bit and haven't found exactly the answer I'm looking for.

I'm spending a bunch of time and money to get the boat in good shape. Its a great boat and from everything I've read here I think I'll be really happy with it. I don't want to go through all this work only to find out I really should have raised the transom when I had the chance.

Whats the advice?

My recommendation would be that if you want a safe boat to go to a 25 in transom. If you use the original transom. Test it before you put the boat in the water. While the boat is on the trailer tilt the motor about a 1/3 to 1/2 up and stand on cav plate area with out breaking your leg or head. Bounce a little and have someone else watch the transom around the motor mount. If No flexing then the transom is OK. On a 78 original transom I doubt it. Especially after having a 235 HP on it. It is getting hard to find 20 inch motors new that are not clamp on low HP.

[Chaser]

Originally Posted by bly

My recommendation would be that if you want a safe boat to go to a 25 in transom. If you use the original transom. Test it before you put the boat in the water. While the boat is on the trailer tilt the motor about a 1/3 to 1/2 up and stand on cav plate area with out breaking your leg or head. Bounce a little and have someone else watch the transom around the motor mount. If No flexing then the transom is OK. On a 78 original transom I doubt it. Especially after having a 235 HP on it. It is getting hard to find 20 inch motors new that are not clamp on low HP.

I do a lot of work on boats and yes the transom is structurally sound. It was a bit of a surprise what good shape it is in, but also created this problem... If the transom needed replacement it would be a no brainer to raise it to 25", but since it doesn't need any repair, I don't know about cutting into a good part to change things around. The reason would be to give the boat better sea keeping abilities.

[floorboy]

Originally Posted by Chaser

The reason would be to give the boat better sea keeping abilities.

That would be reason enough for me as long as your working on it.

[bly]

Originally Posted by Chaser

I do a lot of work on boats and yes the transom is structurally sound. It was a bit of a surprise what good shape it is in, but also created this problem... If the transom needed replacement it would be a no brainer to raise it to 25", but since it doesn't need any repair, I don't know about cutting into a good part to change things around. The reason would be to give the boat better sea keeping abilities.

What about a Jack plate type permanent aluminum 4 or 6 inch set back . So that you can raise the transom to 25 inches with out doing it structurally. . Or a full splash well with the 20 inch transom. We are only concerned because the 20 ft sea craft hull will allow you to fish in shall we say sportier conditions then most 20 ft boats. Most would never fish any other 20 ft boat in the conditions that you normally see sea crafts fishing. That is why we go out of the way to modernize or standardize the 30, 40 or even 50 + year old best riding boats in their class. If as you said the water line was raised very high? Just putting the propper size engine on there does not mean that the floatation foam is not wet and with the 20 inch transom you could still have a problem waiting to happen. We are only trying to help from our own past experiences. I think I bought my first 20 ft sea craft in the late 1970s and that boat had all the cap rivets coming loose to the point of water shooting up the side of the hull under the rub rail and between the hull and cap into the shelf area next to the forward raised fish box. I could have blown the whole cap off into my face when I was young and crazy.

[Chaser]

Thanks for all the input everyone. It sounds like I should do it.

A bit of a disclaimer I don't fish! I like this boat though for its ability to handle a bigger sea state than other 20 foot boats. We plan to use the boat as a chase boat and support vessel for my business and the racing program I run, so its got to be able to handle conditions that might be considered "sporting" for some...

[workinpr0gress]

Originally Posted by bly

What about a Jack plate type permanent aluminum 4 or 6 inch set back . So that you can raise the transom to 25 inches with out doing it structurally. . Or a full splash well with the 20 inch transom.

That is what I would be thinking. Jackplate, splashwell. Jackplates are a useful, beneficial toy.

When my transom starts going I'm going to to cut my bracket down to 18" and widen the chamber. Then it's getting a hydraulic jackplate.

[scnewbie]

Raise the transom. My SC was redone in 05 by previous owner, new pourable transom, but left at 20 inches. Now I want to enclose and bracket due to water pouring in through the notch bc of heavier four stroke. You won't regret raising it, but you will regret not raising it.