That was Potter's early transom closing system that allowed installation of a bracket without redoing the transom. That's a Hermco bracket so it might have enough flotation to at least offset all that weight.

You're right to be concerned about motor weight, because this boat was designed for the 2-stroke motors made in the early-mid 70's! If this was a CC model, I'd be suspicious that your CG is too far aft, but some of the later SCI Sceptre's seem to be bow heavy, maybe because they used plywood in the decks instead of balsa core, so that configuration might work ok on a SeaCraft Industries model, 1980 or later. 78 is a Potter model, so should have balsa core in the decks. If you do a sea trial on it, I'd trim the motors up as far as possible, retract the trim tabs all the way and see if it has a tendency to porpoise. If it does so easily, that's a sign you need some more weight up front to compensate for that half ton of weight sitting 30" aft of the transom!

Estimate CG Shift from a Non-Bracketed, Non-Twin
 

Our performance moderator, Bushwacker, reminds us the engines when Moesly designed the SeaCraft outboard engines were considerably lighter than today’s engines and particularly four strokes. Bushwacker has also been very candid sharing what he has learned in using his 20’ Seafari conversion to a full height transom with a Hermco bracket for his ETEC 150 HP, including his pros, cons, and cautions.
Here's a bit of science to assist in estimating center of gravity shifts for their engine and bracket decisions. Please realize the attachment is a tool primarily for estimating the change in center of gravity of adding or relocating heavy equipment, not a precise center of gravity calculator.

If the link doesn't work, I think the date of my post was 9-24-16, if you care to search for it

Estimating CG Shift rev7 pdf.pdf

Link to Estimating CG Shift
 

Maybe this will work

http://www.classicseacraft.com/commu...0&d=1474774043

Dginge, when you talk to mike tell him ryan says hi. I was going to buy this boat last week and I think it's a good deal for the money. The engines are clean with low hours, the floor is solid, and the fuel tank was redone mid 2000s when the boat was repowered. Overall it seemed pretty solid and I just may be regretting not following through with the sale.

As far as the weight I did not seatrial the boat but I think the bracket will have plenty of flotation. Really the only negatives I saw were trailer related, and they weren't major.

Thanks ryan
 

Thanks so much Ryan. We are excited. Headed that way soon. Would you mind if I called you at your convenience. Thanks
My cell is 2514636662


QUOTE=Ryan;253132]Dginge, when you talk to mike tell him ryan says hi. I was going to buy this boat last week and I think it's a good deal for the money. The engines are clean with low hours, the floor is solid, and the fuel tank was redone mid 2000s when the boat was repowered. Overall it seemed pretty solid and I just may be regretting not following through with the sale.

As far as the weight I did not seatrial the boat but I think the bracket will have plenty of flotation. Really the only negatives I saw were trailer related, and they weren't major.[/QUOTE]

That's a lot of caulk/gap between bracket and transom starboard side. Gotta know why. Would be a nice ride if it checks out.

Dginge, I'll pm you my number

I thought the exact same thing but the hermco bracket is more straight
And the transome of course has a curve. Not sure why but
Evidently the transome is solid. Keep thoughts coming. Thanks

The transom factory out of the mold is flat but a lot of the time when people redo the transoms they sag outwards and then once the new wood or core and glass work is done it stays crowned that way. You really need to add stright edge braces to the back when the new core is bonded in or it will end up with the curve. Not that it will hurt anything except now it doesn't match the bracket perfectly at the swim platform. I have seen this before and other than the calk pulling away it shouldn't be a big deal. Just make sure it is actually solid and not getting soft and bowed from the weight of the bracket and motors pullin at it.

Thanks so much for the information!! I cannot tell whether the transom has been
Redone or not and the guy I bought the boat from doesn't have a clue. He bought it from a old timer that refit the boat in 2004 with the new engines and
Fuel tank. Maybe the transom has been redone. Would a survey be worth it here? I'm no boat builder but I know how to tap the transom with a hammer with a rag over the head! Ha