1977 Ski Nautique Ressurection

I'll take better pictures of the current progress, and shrink the 1+mb pics that I have of the muddy mess that were the stringers. I don't have my usual sunday boat day tomorrow, it's my daughters birthday. Is photobucket the best site to shrink pics, or is there a free way?

I shrink all my pics using MS Paint.

Bummer that you paid for a stringer repair that wasnt done properly- looks like youre doing it right this time. If you could post up some pics for people to see what a $2k stringer job looks like, that would be helpful.

That is normally exactly what I would do, but I feel like I'm just as at fault. I shopped around for the absolute cheapest solution for my problem, and I got what I paid for. I'll post the pictures of what I pulled out; pressure treated wood with straight cuts not scarfed, fiberglass that didn't really stick to anything, etc. etc.

So I primed the oil pump, finished off the motor, mated up the trans, hung it from my swing set (as my girls call it), and got the motor in the boat! Huge step, at least mentally, to have the two pieces together at last! I think I've got everything where it needs to be, but of course I have some questions that need to be answered before I go any further. I don't want to rely on any dimensions from the old, ratty stringers (and I didn't take enough before pics), but I think the flanges are aligned close enough to mark the holes, move the motor, drill the holes, treat them with cpes, etc., tighten everything down, and THEN align the motor. My first question is, how long should the exposed portion of the shaft be? From the end of the flange to the beginning of the gland nut is 7 1/4". Too long? The motor came close to aligling without any adjustments. The prop rotates about 5/8" from the hull. Too close? Prop rash waiting to happen, or normal? Well, I can't seem to upload pics right now. It says 'access denied'. I'll post this and try again in a sec.

Yep, the motor's doghouse is cut out so the pylon can be cleared when opening the box.

There is not a lot of room eve from the factory. With my fly high pole on, I have to be careful when I raise the motor box so I don't scratch my vinyl on the box.


You are definitely getting there now.

I just went out in the rain to measure the outside shaft again. There is exactly 1 7/8" exposed from the strut to the prop. Considerably more than your reccomendation, TRBenj, but less than it was running with before, based on the shiny area on the shaft. also, exactly 3/4" from prop to hull. By the way, how come it's taking so long for someone to pipe in and say, " my wife says 7 1/2" is plenty of exposed shaft." There. I said it.

David,
What size is the prop that is giving you the 5/8" hull clearance?

Sorry Peter, my measurement was off. It's 3/4". Still too tight? The prop is a 3 blade, but I don't know anytthing else about it. It's dinged up, so I need to get a used one soon anyway. What prop is a good all-around one behind a 300hp motor?

charger496 wrote: Sorry Peter, my measurement was off. It's 3/4". Still too tight? The prop is a 3 blade, but I don't know anytthing else about it. It's dinged up, so I need to get a used one soon anyway. What prop is a good all-around one behind a 300hp motor?

I would say that 3/4" is marginal- and I bet Pete will agree. The rule of thumb is 10% of the prop's diameter, so 1-1.5" on a 13". The most important thing to realize at this point is that you shouldnt be basing the placement of the engine on the prop clearance... the geometry of those things should fall into place if you maintain the factory set up (engine and strut location). Your goal should be to get the engine back in the same place it came from the factory. Use all the clues you have at your disposal to do that.

Later, if you want to optimize your clearances, then do so. Tweaking shaft length is the easiest way to accomplish this. Everything Ive read indicates that minimizing the strut to prop hub clearance (leaving just enough to get a puller in between) will optimize smoothness and performance.

If you can identify your current prop, that would be beneficial. It should have some dimensions and a brand stamped on there somewhere. Sometimes its on the face of the hub, other times along the body. The original prop would have been a 13x13 Federal.

Prop selection is a bit of a science... knowing how you use the boat and baselining your current performance (getting accurate performance and RPM numbers with a known prop) is a good first step in picking out a wheel that will work best for you. If you can clue us in on those things, there are many here who can point you in the right direction.

That being said, many here have been very happy with the performance the new CNC 3-blades offer. The Acme 540 is probably the most common on 351w pwered boats- stock and warmed up ones alike. There are several options though. One advantage to the modern Acmes is the increased aft blade rake- this will increase your hull to prop clearance.

Ok, so the prop is a Dyna-jet 13RH15. I don't know enough to guess what it's strong pionts are, but it's not as dinged up as I thought. I did some very gentle massaging with a small hammer and dolly to get the blade tips in shape. The test-run will determine if I buggered it up. The pros put them in a jig, I know. I'm sure folks are cringing at the thought of taking a hammer to a prop... Anyway, after a couple hours of aligning, the flange still has about .10" of runout, so I'll pick up where I left off later. End of shaft: 1 3/4" or less. Hull clearance still 3/4". I WILL break-in the cam next week! My wife thinks I'm about to move my stuff to the boat and live there. Couldn't imagine doing this without her being so understanding.

Marine distributors dont have a vacuum advance because the engine is always under load (no coasting down hill). If you pop the plate off that holds the EI conversion module, you'll find the weights and springs that determine your advance. You should start with about 10 initial and end up with about 34 final.

Definitely dont spend any money fixing that 13x15 Dynajet, by the way. That is pretty far from the size you need (13x13) so its unlikely you'll be able to use it. Thats probably whats throwing off your hull clearance numbers. I doubt anyone here will have had experience with that particular prop on your hull, so even if you get performance numbers for us, we wont be able to correlate them to something we're familiar with very easily. Id put a new one on your xmas list.

By the way, someone posted a couple weeks ago about hot-glueing these neat little clips to the stringers so you don't need to use screws. works great until they fail. Next time I mix some cabosil, I'll get 'em to stick.

How did you build your front floor? It looks translucent, and there appears to be no foam.

charger496 wrote: The car is a 1971 Dodge Charger with a 383 stroked to 496 or so. Dyno'd at 530hp/630lbft. The front floor section of the boat is 2 layers of biax and a layer of cloth that I made on a piece of plastic covered plywood, then made a cardboard template of the sections next to the recessed battery box. Cabosil glues it to the stringers and more biax will tie it into the hull.

Nice idea on the floor. I'll bet it drank resin like a sailor on shore leave.

It's alive!!! Got the timing close enough to get it to fire, broke-in the cam for 25 minutes or so. The new engine sounds great and I can't wait to get it on the water for an end-of-season test run. Just an hour or so to see what bugs I might need to work out over the winter. The rear of the oil pan has a slight leak that I hope will magically get better. Supposed to rain the next couple days, so maybe before the weekend.