This is why I love this site and it's inovation run amuck.
Thanks guys.

Now I have to catch my buddy with the 28-Sportsman and measure it up and see if I have the room for a standard prop shaft, gear box, engine setup and weigh my options. I hadn't thought about tilting the engine to match the prop shaft angle. Mounted a foot or two from the transom my spark arrestor sits about 4" above the deck but the bilge runs deeper the farther forward you go so my small block chevy should fit right up between the two 50 gal gas tanks on either side of the steps down from the weather deck.

Joe,

I do not have a lot of experience with the newer VP drives, and I am pretty sure they went to the merc style shift and a rubber coupler at some point. Their newer drives are composite, which is always nice if you are in saltwater, though (at least) initially they had some problems with them.

I am not sure what you mean by "overhanging transom", but I can tell you my old boat had a near vertical transom with a VP280 (same thing, just no power trim) on it...

You could always just go hog wild, and put a jet drive in it... I just picked up another ski, and was pondering mounting the whole power train in the M in the center as an auxillary / booster, just for the hell of it. Would really be pointless, but cool none the less. I am not sure that the hull on the M draws anymore water than the hull on my ski. On the upper Chesapeake, this would come in real handy...

-Shane

Your can likely get a VelvetDrive to fit the GM block. They have a section that contains the reversing gear, and after that a section that contains the reduction gear. You can get a wide variety of reduction ratios. Early M's didn't use the reduction at all, but you will probably want 1:1.53 or 1:1.91. First, you must determine what size prop you can fit. Unless you are racing, you probably want the largest prop that will fit, and then choose the ratio to drive it properly. Remember, props are most efficient when the pitch is greater than the diameter, up to about 1.4X.

Been there, done that. SEI has nothing to fit my gimble. This old MercCruiser II has an entirely different transom mount from the Alpha's that followed it.

Given the problems I've had I am leaning towards something much more hard working and reliable like a tranny system. Velvet drive or a V-drive if I don't have the room to put a velvet in her. Otherwise VolvoPenta has some I/O models that do not want exhaust and cooling water run through them. I am only pushing 225hp out of a 327 GM block, thinkin I should have gone with a 350 small block. Dual outboards would be nice but the cost is beyond what I can do right now.

I really load down this 26' when I have 6 divers and their gear aboard. I don't think loading has been my problem but it might have been. I believe that most of my problems have been trusting mechanics to "do it right." I am looking at converting because I have used up all my spare Mercruiser parts and they are real hard to come by anymore. I can not afford to break down at the beginning of the season again.

If you know the sizes and pitches, and the rpm's and speeds that you got with them, it should be possible to make a good guess at the proper size for your boat. You operate more like a crewboat, and will thus want the larger prop to get the required thrust at reasonable engine speed. Check John's Marinette website to see what they used.

The velvetdrives are completely bulletproof, and are used in commercial applications all over. Marinette did it right the first time, and you might want to just copy the setup that they used with your hull. The tranny/shaft/strut/prop combination is impossible to beat for rugged and easy to work on.

I assume that your boat was always a Mercruiser and so the engine is far aft. That means that you would likely need a V-drive, with the engine reversed, the transmission forward, and the shaft running back under the engine. This is in fact in my opinion the perfect setup, you can get at everything. It is only a couple of gears more complicated than the straight shaft. You would have to add a packing gland to the hull, which means that the engine comes out anyway. You will need thruhulls for the engine coolant and an exhaust system.

I know that you have been waiting for this, but since you use this boat commercially, you might consider converting to diesel. I know a guy who has done it a couple of times, and has some info at http://web.me.com/dougmr...nversion_to_Diesel.html

I would only mention that there are a lot of really good deals out there on Marinettes in fine condition. It might make sense to just start over with a new boat that has what you want.