Thankyou for the replies. I assume when you say IC motors taht is internal Combustion.I live in country Victoria so the noise would not be aproblem. I think I am going to have to do a bit more research into how the electric motors fit in and batteries etc. Am only up to early painting at the moment so have a way to go.Thankyou once again.Regards Keith

HI Keith
Welcome to the site.
I have restored a 34" Fireboat and had to remove all the oil and grease from my hull after its use with a diesel engine. Not the biggest of models and needs to be kept light if you want to see it get on the plane. 😀
As you are aware IC engines are not commonly used and there are few waters who allow IC engines. Your choice then is between brushed or brushless motors. Power could be SLA, NiMh or LiPo. Really comes down to cost as there is quite a difference between brushed and an SLA and brushless and a LiPo. 😊
If your hull is like mine was the prop shaft will probably need some attention having run with an IC with little or no lubrication. I had to replace mine as the bearing bushing at the engine end was almost none existant. Also I had to repair and recover the outer skins to make waterproof.
It you post a bit more info about what equipment you already have and your budget it will be easier for the Forum to give you more relevant help.
Good luck with the rebuild, why not start a build blog to share your experience? 😀

hello Keith
in my 34in fire boat I use 540 motor turning a 35mm 3 blade prop .
on 7.5 batt 20amp esc runs OK . on this set up Larry....