Boat Project

[Dieselboatman]

Hello everyone

I am looking to get my first boat project as something to spend the evenings tinkering with

I have some experience with boats but mainly outboard setups apart from a little bit of work on an inboard engine (diesel mechanic by trade and fabricator as hobby)

But I personally would like an inboard setup

I have seen a few 18~22foot boats with inboards (rather like the Colvic 20 and Seaworkers personally)

However I have seen a few others with sterndrives

What puts me off a sterndrive is the coat however, if i had to replace it


What I want to ask is this....

If I had a sterndrive boat, would it be possible to make a plate up to cover the sterndrive hole, and fit a standard inboard gland and then simply mount the prop on the back of the boat? And make up a bracket and fit a rudder?

Would it work? Or if not is there a way to make it work please??

Just thinking it would be an option, even if it meant creeping engine forwards a bit for gearbox room and a short prop, could even make a box instead of a plate to make a little more room for the gearbox?

Thanks in advance

[ChrisH]

I'm no expert, but as I understand it most boats with a stern drive have planning hulls. So the prop needs to be below the lowest point of the hull at the transom. It might just about work if you were going to poodle at river cruising speeds, but I would think that might be touch and go.

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[Ianfs]

Hi Deiselboatman and welcome to the forum.

Wow, this is quite a complicated question to answer without going into great detail, but I'll throw in some of my experience.
From the sounds of it you are not looking for a fast boat, but instead something like a small fisher to maybe take out fishing and preferably diesel as that is what you know best.
You are right, the cost of replacing a stern drive is expensive, but in reality most from 1980 onwards are pretty tough and for someone like yourself fairly straightforward to repair if necessary and there are mostly 2 makes, Volvo and Mercruiser. Most faults are usually things like bent shafts or bearing seals but if the boat has a good history and the oil changed regularly it should be fine. Stay away from one with milky oil, no history, lots of barnacles and rotted metal etc.

The idea of sterndrive is to free up boat space by sticking the metal lump on the transom out of the way. You could in theory make good the hole where the transom shield went with ply and glass and move the engine forward then make a hole in the bilge for a prop shaft, taking care to glass it well in, tilt the engine and connect it all together adding a rudder at the same time. However, heeding something Chris wrote is that there are a lot of planing boats out there and planing hulls wander at low speeds because they purposely don't have a keel. But I suspect I am teaching you to suck eggs here and you already know this.

Colvic have sorted the shaft drive out by mounting the engine in the cockpit with a cover and tilting it to fit on a prop shaft, but again that Seaworker you are looking at has a displacement hull with a bit of a keel so will work well at low speeds.

So all in all, yes it could be done, but you are going to upset the balance of the hull and lose space. I would think that someone with your experience and expertise would be better off buying something with a shaft drive already that has maybe a duff diesel engine or even a blown petrol engine and converting it to a diesel.

Just a thought.