convert jet boat to outboard, can it be done?

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Snouch

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Hi
I have a 1995 14 footer baja splash. With motor blown (block has a whole you can see connecting rods). Can't find a cylinder block as it is no longer available. My question is can I put an outboard motor on this boat. And if so what do I need to do this project. Currently has a 120 sport jet engine. Any help or leads would be awesome.
 

Ned L

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Can it be done? ..... Sure, anything can be done. However,... You would be moving the center of gravity back quite a bit which could change the performance quite a bit. The bigger issue may well be that as a jet drive boat the transom has (and needs) really no structural strength. The transom is exactly where all the strength needs to be for an outboard.
 

Snouch

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Thanks for the reply. I was on thinking this because there are no replacement parts available and the boat is in good shape. Maybe adding an outboard would be an option. I have seen photos of seadoo boats with outboards on them. And I think it would be cheapr fix. Im not looking for anything fast. Even 50 to 70 hps outboard. Is there a bracket or kit for this conversion.?
 

spoilsofwar

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Doing it would be a massive undertaking in custom fiberglass fabrication. I've never seen a jet boat that had a transom anywhere near suitable for outboard bracket installation. In any event, you would spend far more doing it then that boat is worth, even if it's otherwise pristene. At the end of the day, it's your money and time...

Don't Mercury sport jets use outboard powerheads? Can't imagine it would be impossible to find a replacement block if that's the case.
 

jbcurt00

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Its a typical PWC jet pump motor isnt it, just in more of a boat shaped hull?

Wouldnt grafting a different PWC jet setup into your hull be easier and less costly then conversion to OB?
 

Scott Danforth

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The sport jet in there is a merc/force 90 hp or a merc/force 120 hp power head.

There are a few on ebay
 

Snouch

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Can't find one on ebay thats the same. But I have seen lots of outboard motors installed on seadoo jet boats. I dont know much about fiberglass but I do notice the back of my boat is pretty thick maybe I would be able to add a bracket on the inside and outside to hold the outboard. Not looking for something fast. Maybe 50 or 70hp.
Anyone who knows about this type of project could give me some advice and steps on how to go about this. Thankz
 

spoilsofwar

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Sure, there are plenty of outboard converted seadoo jet boats on YouTube. We have no way of knowing how solid the conversion is, other then a proof of life video. Most of the ones I've seen are considerably larger then your 14ft Baja, which better offsets the increased weight of an outboard at the stern. They also include considerable custom glass work, which you've not indicated you're willing or able to undertake - not a bolt on outboard bracket. If you're able to do the engineering an fabrication work required to make it work then it will work... But then again I suspect if you were able you'd not be asking here how to do it. How will you cover the jet intake on the bottom of the hull? Will you reshape the entire keel?

My suggestion is to find a suitable replacement sport jet motor, or to scrap your boat for parts and find a complete boat ready to run.
 

Snouch

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Im going ahead and trying this conversion. I will be ahead glass to the hole from old engine and reshaping bottom of old engine area.
If any advice on thicking the transom area would be great. So far I have sanded rear transom area. Will be adding another board against old transom.
 

jbcurt00

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1.5in of wood transom, wrapped in glass 3/16-0.25in each, for a total of 2in of transom for the OB clamps.

And take note of Neds advice above, the sport Jet doesnt require a well supported transom like an outboard boat would. Needs to be well tied into the hull, not simply bolted together on a thicker tranaom.

Better find a motor 1st, the sport Jet isnt a typical OB height transom.

Good luck w the project
 

sphelps

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How about some pics ... Is there a top cap that can be taken off ?
 

Snouch

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I have sanded off gel coat from rear transom area I'm thinking of adding a half inch board wraped In glass then bolted through transom with a wide steel plate on inside. I will be Closing the hole from engine area. Any suggestions or advice again will be greatly appreciated. Thanks
 

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Snouch

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Hi I'm adding half board in back and half in inside to thickin the transom area to add a bracket for outboard.
 

lckstckn2smknbrls

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How is the transom construed? How thick is the transom? Is it just fiberglass or does it have a wood core?
 

fhhuber

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Carry a bunch of 5 gallon plastic jugs all tied to the hull... You might need the flotation when the outboard rips the ransom out.
 

spoilsofwar

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Well good or bad, thanks for coming back to this thread to complete the story. Let's see that video now and some pictures...
 

Snouch

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Still haven't taken it out yet. Also i tried to upload photos from my phone and always getting an error. But planning this month to try it out. I will have a video of the out come.
 
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