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yachts
06-12-2002, 11:20 PM
of a jet drive into a 1970's vintage 24' Sea Ray hull. (SRV 240 sportbridge model, dual helm set up). Would also like to install the jet behind a 6.2 or 6.5 GM turbo diesel. This would be for salt water use, south Florida area. I love the boat, but hate the I/O and really hate outboards. Have lots of boat experience, but I know absolutley nothing about the drawbacks of jet drives, especially when mixed with salt water, and diesels. Any opinions, suggestions, and/or guidance would be greatly appreciated.

Rusrog
06-13-2002, 07:19 AM
First of all....
I have a couple of questions....

What in particular do you hate about O\B?
What in particular do you hate about I\O?

I have heard very few if any good things about either the 6.2 or 6.5T engines. I know several people with them and all can't stand them. No power and worse than normal gas mileage to boot. There are some jet drives that will do the trick but if it were me I would seriously consider trying to find a good MerCruiser package to drop in for several reasons.
You already have a hole in the transom.
You don't have one in the bottom of the boat. (For the jet intake)
A stern drive will be more efficient and most likely perform better.
The best bet would be to fill that hole in the transom, install a Stainless Marine Transom bracket, and bolt on a pair of O\B's but that doesn't sound like your cup of tea. Look through the Mercruiser catalog and I bet you will find something there that will suit your needs.

Good luck

yachts
06-13-2002, 09:25 AM
Rusrog, thanks for your reply. Answer to your questions, From personal experience, and just simple observation(observation, obviously biased by the experience) outboard motors seem to spend at least as much time on the rebuild bench, as they do hanging on the back of the boat. I like the power end of the I/O's however my boat lives in the water, not on a lift. That outdrive seems to disolve in the salt after awhile, not to mention the seals on the hydraulic rams, etc. This is the reason I just pulled the unit off the rear of the boat, then discovered the typical Sea Ray transom cancer, so pulled engine,etc, to prep for a transom replacement. So this seemed like a logical time to look at power options. A Inboard with vee drive has not been ruled out yet either. Obviosly this increases the draft in an area known for rather shallow water. As for the 6.2/6.5. I have no experience with the 6.5 but have been told they cured many of the ills of the 6.2 which came in two "flavors". The "C" vin code is undoubtedly a pile of junk. The "J" vin code that was installed in the government issue Hummers, and GM light trucks manufactured in Canada is rather highly regarded. I have one in a one ton dually dateing from 1982 with 137K on it. I keep oil and filters changed regular and it has been a excellent experience. It is no speed demon at around 100 hp, but very reliable and economical. As I am replacing the transom, I'm gonna be cutting holes somewhere, either in the bottom, or the transom again. How well does the jet unit stand up to continual immersion in salt? The same as a outdrive?, better?, worse? The opinions on that could sway me one way or the other. Again, Thank You for your reply, I appreciate the opinions, and food for thought.

pyro
06-13-2002, 11:00 AM
This sounds like a very bad idea. As it is, a 160 hp jet drive is barely capable of getting a 16' boat on plane with four passengers. That thing would be full throttle, making all kinds of disturbance behind it, but it would barely move. Jet drives are too inefficient for large, heavy boats. Jets work best for lightweight sub-20 foot boats, and even at that, a 300+ hp bigblock jet drive on a 18 foot boat isn't any more capable than the same boat with a 250 hp outboard. Once your transom has been PROPERLY re-built, but the outdrives back on with all the right anti-corrosive measures.

Saltwater eats ANYTHING. Nobody is safe...

delawarerick
06-13-2002, 11:27 AM
Duskies in the 70s had a 24 foot center consel with a 351 big block ford hooked to a jet drive. This idea and design was abandoned due to impratical aplication in salt water and that was where these boats were designed to run. The constant fear and reality of electrolosis made these boats disappear. The jets were removed and brakets and outboards or twin outboards were installed. Mind you I respect your idea but look at the praticality of it. Later Rick

BarryStrawn
06-13-2002, 11:56 AM
Yachts - Suggest you visit http://www.boatdesign.net

tonga
07-19-2002, 09:09 AM
Why not use a pair of outboards with power tilt?
The power tilt should keep them out of the salt water when not in use!
and a good flushing system and a rinse should keep the salt gremlins away!
TONGA

Techno
07-19-2002, 11:28 AM
Changing a IO or OB to a jet is a lot of work. The jet has a big hole in the keel and is built this way. The others aren't built to have this hole in thier keel. This is about like putting an IO in a boat that only has the structure for a OB- but worse.

Stick with an IO and epoxy all the holes in the transom up real well.
I would suggest looking into an OB so you have facts and not an opinion to base a desicion on. I would suggest an OB for a replacement due to many reasons. But you need to find out if an OB will run for the time you expect it to run before a rebuild. If re-build time is your only dislike you may be surprised. They also have jet OBs but a propped one would probably be better.
Look at the Offshore outboards, they have something to do with salt use, not sure what though.