jet drive to outdrive..??

[msswindled]

has anyone ever changed out a pump for an outdrive. i've toyed with the idea myself. just curious if anyone has tried it and what it took to get it done.

1974 wriedt spoiler 19' 454/berk jc

[Fonz69]

Dont go to the Dark side

You'll never come out alive

Seriously from what I understand if you want a jet boat use a hull that was made for a jet and the same goes for the outdrive.

I am sure it can be done but the cost just does not seem worth the hassle when there are plenty of each of the types of boats to go around

[whipper]

has anyone ever changed out a pump for an outdrive. i've toyed with the idea myself. just curious if anyone has tried it and what it took to get it done.

1974 wriedt spoiler 19' 454/berk jc

Theres a company that has a kit to do this. What they do is make the jet a surface drive. Cant remember who they are? They used to advertise in the back pages of Hot boat all the time. Last or second to last page every issue pretty much.

[Darkside's Calling]

Biggest problem is having to reglass the hull from the jet intake and transom pass thru. Most I/O's are transom mounted and need additional thickness for support. The OMC 400/800 Stringer mount units can be adapted after glassing the intake hole. My '80 Tahiti 18 ST was converted to the OMC 800 and the transom boot covered the transom hole.

The biggest advantage of the I/O is the fuel efficiency over a jet, but due to the size of the outdrive it's VERY difficult to get the prop centerline anywhere close to the keel. My Tahiti runs about 3 1/2 to 4" below... There is not enough transom to raise it up much more than an inch or so from where it is.

[BIGA]

[QUOTE=Darkside's Calling;1822914]Biggest problem is having to reglass the hull from the jet intake and transom pass thru. Most I/O's are transom mounted and need additional thickness for support. The OMC 400/800 Stringer mount units can be adapted after glassing the intake hole. My '80 Tahiti 18 ST was converted to the OMC 800 and the transom boot covered the transom hole.

The biggest advantage of the I/O is the fuel efficiency over a jet, but due to the size of the outdrive it's VERY difficult to get the prop centerline anywhere close to the keel. My Tahiti runs about 3 1/2 to 4" below... There is not enough transom to raise it up much more than an inch or so from where it is.[/QUOTE
x2 good info

[Darkside's Calling]

I'll try to post up some transom shots of the Tahiti tonight when I get up (work graveshift...)

[msswindled]

yeah, its my first jet. when i was a kid, i always liked the loud flashy boats with the chrome and the rooster tails ! but after owning one and learning more about them and how ineffiecient they really are, i want a i/o setup. it just takes way too much power, ie. money, too make fast running speeds in jet. its a blast to drive and like the hull and cockpit, but think i might sell it and buy something with an outdrive.
i was just thinking how cool it would be to keep my boat. and my 454 and an outdrive would freakin scream compared to my berk jet ...

[msswindled]

trying to attach pic..new user here !

[WATERWINGS]

You mean.....like THIS??

[Darkside's Calling]

That jet ski is scary... I'd hate to think what would happen to anyone who fell off while it was running!!!

Anyway, here's a couple of pic's of the Tahiti I/O:

Prop shaft is just a "little" below the keel line, there is no way to raise everything enough to bring this up even close...



This one shows the size of the boot the OMC stringer mount I/O uses, the boots do dry out and crack...


In this one you can kind of see the opening, if you look really close you can see the Berk tramsom plate screw holes right at the cut line


last couple of shots, this is what it looked like when I tore it apart for bottom work... not sure if I'll keep the paint or strip it and see it fhe original gel can be saved

[msswindled]

your set-up is exactly what im talkin about. very sweet ! so now i know it can be done. how much top end did u pick up with the outdrive? also, how did u seal the intake hole? is there a plate you can buy or did u manuf. the parts yourself? very nice ride !

[150aintenuff]

find an arneson surface drive...you will be happier.... that omc is burried and even though im sure its faster than the jet, it still is far from desired and most are not trimable..

[wideglide55]

http://www.arneson-industries.com/
Here is what you need.

[Darkside's Calling]

your set-up is exactly what im talkin about. very sweet ! so now i know it can be done. how much top end did u pick up with the outdrive? also, how did u seal the intake hole? is there a plate you can buy or did u manuf. the parts yourself? very nice ride !

I bought it with the I/O in it already, intake hole was glassed over, and it is most definately "buried", probably 6" below keel!! It's only good for about mid 60's in current trim, and that's with an Desktop Dyno estimated 340 hp. Mine does have trim, in the last pic look right at the bottom of the motor and you can see the trim system, it's an electric drive mounted on the fromt motor mount that tilts the whole engine and drive package.

You'd probably be better off selling you boat intact and shopping around for one that already has an I/O, they are out there, had a 20' Centurion with a SBC/Merc I/O that was really clean on Craigslist for $3500 a few months ago. If I hadn't bought my Eliminator I would have probably bought it.

My recomendation: Don't do it... the OMC 800 is only rated to 320 HP, I'm already past that, and planning more. A replacement (used) 800 outdrive is $2-3K, and a complete OMC 800 with mounts, bell housing, etc runs about $5K, if you can find a complete set. You may have to buy another boat to get everything. The Merc Blackhawk drive (a shallow I/O style drive) is an option, but again not cheap. A Merc I/O such as the Bravo would probably be easier to find, but requires the transom to be sealed and beefed up, and would have the same issue with being buried when running.

You might talk to one of the jet pump guru's (pm sent with a recommendation) and talk set-up on what you have to make it more efficient and maximize what you already have.

If you were closer I'd sell you the Tahiti as is for a reasonable price, as is...

[boatermike]

solis might have been the name of the jet drive conversion to surface drive. i think it had problems holding bearings