'85 Sceptre, project planning

[Cutiger]

All, I'm excited to have the Sceptre in the driveway waiting on me to get started. Right now, I'm looking closely through the layout and starting to plan the process of getting it back into running condition. I'm trying to read through old threads to get different ideas as I can, it's just very time consuming to go about it that way. If anyone has bookmarked redo threads or discussions that you find particularly applicable or important to this one, please feel free to post up a link.

My goals for this boat are to redo the important, necessary systems to get the boat back on the water. Once that is all completed, I can turn attention to cosmetics as needed and as funds allow. I intend to put together a fishing boat, not a show piece.

My anticipated order of operations:
1. Remove fuel tank to have pressure tested. Proceed as needed based on results
2. Remove remaining fuel system
3. Strip the old wiring
4. Put a battery to these old motors and see what kind of shape they're really in while I'm waiting on fuel tank work.
5. Recore tank hatch, repair bow soft spot, repair old screw holes, nicks, dings, etc.
6. Reinstall tank and all fuel lines
7. Rewire and install electronics
8. Re-rig old or rig new motors

Now, a couple thoughts and questions that immediately come to mind. Some I know have been widely discussed.

If it ends up not taking too much money to get them running fine, I want to run the boat with the old 140s just to get a feel for weight on transom, how the boat runs, etc. That'll let me make the best decision for me on repower choices. But I'm considering the single vs. twins debate. Performance, efficiency, and cost vs. having twins for the really long offshore runs we have out of Charleston. I think the flotation bracket and closed transom is out of the question right now simply due to the cost.

Secondly, battery location. Refer back to engine debate. With a single, keep them in the transom corners. With twins move them forward, but to where? I haven't identified a good place for 3+ (2 starting and a house minimum) batteries for a twin engine setup.

Really I just need to make these two particular decisions before I start installing the new fuel system and the electrical. Feel free to weigh in on order of operations, the engine and battery debates, or any other suggestions of things to pay particular attention to. Or don't weigh in at all, sometimes it helps to type it all out and have a conversation with myself like a crazy person

[Bushwacker]

Maybe some current owners can confirm this, but the later model non-Potter Sceptre's have a reputation for being somewhat bow heavy, evidently because SeaCraft Industries used plywood instead of balsa core in the decks and cap, plus the fiberglass seat boxes also add some weight forward. Some folks doing restorations on them have reported finding pig iron weights under the deck in the stern, evidently put there as ballast to compensate for the bow-heavy condition. (You might be able to check for the presence of those weights by moving a hand held compass over the area to see if it's affected by the iron.)

Bottom line is that I don't think you need to worry about moving batteries forward. The boat would probably even tolerate a heavy 4-stroke motor mounted on a bracket with no adverse effects, although if it did prove stern heavy in that configuration, you would have the option of pulling up the deck to remove the ballast weights.

One comment regarding the twin 140 motors . . . my understanding of how OMC got 140 hp out of what used to be a 135 hp powerhead is that they moved the top rings closer to the top of the piston. (This has a slight effect on when the intake and exhaust ports open and close, similar to changing the cam timing on a 4-stroke motor.) The net result is that, due to the thinner ring lands at the top of the piston, they are a bit less tolerant to detonation, so it's real important to NOT run low octane fuel in those motors! If they have good compression, I'd try to run at least 90 octane non-ethanol fuel if possible. You could also run 92-93 octane premium E10 gas, but with the E10 gas, if you happen to get enough water in it to combine with all the ethanol, it will separate out and drop the octane level by 3-4 points, which can be fatal to a 2-stroke! Since there are no valves to rattle, you can't tell if you have detonation in a 2-stroke until it either destroys the rings or blows a hole in a piston!