Nautica 22 Jet repower questions

[Au551e]

G'Day all,
Been a lurker for a while and am impressed with the quality of the replies to others questions.
Here's mine. Just purchased a 22 Jet that WAS equipped (no motor) with a Yanmar 240hp diesel. The Yanmar is way out of budget to put back in. Has anyone done a diesel to gas conversion, if so what? Any pictures? The drive is a Hamilton HJ211 by the way.
Any advise would be greatly appreciated.

[Pete7]

You need to have a chat with your New Zealand cousins because they are real experts on jets:

http://www.nzjetboating.com/yabbse/index.php

Pete

[Au551e]

Thanks for the start Pete, I am struggling to find any good info.

Cheers

[Pete7]

The danger is you will spend hours on that website anyway welcome to Ribnet btw

Pete

[Au551e]

I know, have been there for quite a while

[Searider]

The Hamilton website suggests that there is full spares availability for that unit:

http://www.hamiltonmarine.co.nz/inde...lton_Waterjets

I would suggest that you find out which impeller is fitted to your jet (there will most likely be a selection of impellers avialable to suit various engines - rpm / torque) and speak with them. They should be able to suggest what engine RPM and torque characteristics that impeller is suitable for.

212 brochure:

http://www.hamiltonjet.co.nz/include...s_brochure.pdf

If they have a range of impellers available that should open up your choice of engines

[Au551e]

Thanks, I will strip the jet this weekend and find out what I have. As it originally had a 240hp motor, if I stay in that range I would think I would be OK.
Also, what method would be best to clean out under deck diesel tanks to ready them for petrol?

Cheers
Peter

[cosworth mirage]

the diesel engine will have a much lower rpm range than most petrols and hp comes from torque x revs so i would say your going to need more hp on your petrol engine if you are keeping the same impeller..what sort of gas motor you thinking of fitting.

[Mollers]

I had a trip on the Buller River, South Island, NZ in a 15ft Aluminium suicide machine. That ran a tuned 7.4ltr V8 through a Hamilton Jet with a 2 stage screw. By 2 stage, the pitch increases on the 2nd half of the impellor, this perhaps overcame the peakyness of the lump. The race guys run 2 stage impellors I was told.
The acceleration on the thing was neck wrenching.

http://www.adventuretours.co.nz/rive...est-coast.html
These are the gang, but Doc didn't have the big bus when I went with them.

[Au551e]

Sorry for the delay in replying, been away.
As far as the motor goes looking at a Mercruiser 350 cuin, 315 HP with closed circuit cooling as that is how the old motor was setup. Hoping that will give me what i need from a torque
perspective, but I am open to suggestions.
Also, when i attempt to clean the installed diesel tanks, is it imperative that ALL old diesel is removed? Will a little residual diesel mixed with petrol cause harm?

Thanks

Peter