Because we don't own enough unreliable vehicles, we're thinking of adding a boat into the mix.
Actually, it's more because with our one 2 year old (and twins on the way), going on our friend's boat last weekend was quite fun, and we think it might be a fun diversion that we'd be able to do for amorning/afternoon with small kids, and continue to enjoy further.
Of course, I want a twin.
But I'm not sure it's mandatory so much as iLikeTwins.
Our driveway space is limited, but we can fit a 20ish ft boat w/trailer in a corner without getting in the way I think. We have a 1/2-ton Avalanche, so that's about right for towing it anyway. Likely don't want something bigger due to cost and storage concerns, not to mention not wanting to buy a bigger truck just for a boat.
I really have no idea what I'm looking at. General mission thought would be that it would be nice to get something that has the ability to tow a tube or skis. It seems like a cabin area would be nice (especially for kids having naps or needing a bathroom break), but it seems the boats with cabins have virtually no deck space. Definitely not looking at a "go-places" boat, more the $100 hamburger sort since I don't like $100 hamburgers in planes. The twin engine jet ski types also look like fun, but probably be something we'd outgrow in a few years, and might even be too small to start.
Curious as to thoughts. Maybe a cabin sounds nicer than it would really be, especially if it makes it hard to be on deck. Also figuring that needs could change, so I'm not opposed to buying something and upgrading later. With vehicles I tend to just buy what looks interesting and then buy something else later if my needs change.
Lots of potential, what's the budget? Cabin can be done, but it comes at a cost. You don't need much, but you want something to stash the kiddo out of the sun and weather. Many boats have a covered bow that can suffice. If you get into the 23' boat, most of which tow just fine behind a light pick up, you can get a couple of amenities to use it in camping mode as well and still have reasonable deck space.
For safety and efficiency I suggest you go with a modified twin, real main engine of 190+HP and a 15hp kicker 4 stroke outboard as a "come home" engine. With a twin you won't maintain plane on one, so using two big engines unless you want the top HP of both doesn't serve any great advantage and increases your overall costs.
For cost and reliability reasons I would use a straight inboard drive setup. This gives you a modified automotive engine, probably a Velvet Drive transmission, a shaft out through a simple gland that you tighten or repack occasionally to keep the water out, a strut with a simple cutless bearing and a simple taper socket prop. It gets no simpler or more reliable. Trouble is these rigs are not that common anymore, but most of your competition style boats still have them. Correct Craft, an excellent manufacturer used to make a nice 21' that had reasonable space for a simple cabin, high gunwalls, and a straight drive off a SB or BB Chrysler. It would also make a great platform to put a Diesel in since you can work right in the middle of the boat.
The more common drive you'll find is an IO with a geared z leg at the transom. Everything that happens will cost $2500 now a days. Change the boots and lube every year and U-joints every 5 and you shouldn't have much trouble unless you hit something or neglect the anode. The fastest way to cost yourself a lot of money with an out drive is to do a bunch of high power hard turns or start the engine in the full or trailer tilt range. You'll eat u-joints prodigiously and when you lose one it typically shreds the boot which may or may not fill the boat with water while you are sitting there broke down. Not exactly where you want to be. The advantage they have over outboards is again they use a marinized auto/pick up engine.
Outboards used to be a good deal because they were cheap and easy to replace. Still easy, not cheap, a 300hp outboard costs more than your 300hp IO-520. In the 4 stroke - 2 Stroke debate, I'll take a 4.
The big loss risk factor for your maint $$$ it hitting things below the water.
Direct drive, $750, Outdrive $2500, outboard, $1500-$7500 depending what all breaks.
Your big loss risk factor for human tragedy is the prop, and I won't deign it with a $ figure.
Now there is one more drive that mitigates both of those factors and that is a Jet Drive. As with any insurance though, it comes with a premium, and that premium is a 15% cost in efficiency translating torque to thrust.
Personally having seen what I have seen over the years, if I wanted a family boat for fun and water sports, the only drive I would have is a jet pump, plus it opens up shallow sluices and river mouths for use.
You can pick up any Inboard or Outdrive hull and make it a jet with new or salvage parts simply. The outboard hulls will likely take a bit of work making engine beds, but not a biggie, or you can get a Jet leg for many outboards that affixes a pump as the lower unit.
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