Do sterndrives (bellows) sink boats?

I agree with you Marshmat: stern drives can be very useful. I see it here in Cancun and in Latin America where beaching capability is a necessity.

I'll add that Stern drives are cheap compared to the big 4 stroke outboards, uses simple and now surprisingly fuel efficient engines with the electronic injection and fresh water cooling.
I made a study for a client 2 years ago about fuel consumption of gas marine engines between 200 and 300 HP and the Mercruiser 5.0, 5.7 and 6.2L were clear winners over the outboards.

That has been proved later on the water after one year use; a specific consumption of about 195-205 gr of gas/HP/Hour when used at max torque with Bravo II drives, it's 10-13% better than the big Yamaha. After about 1000 hours of use in the year is a big saving in gas. I was at the beginning very skeptic, as I remembered these engines with carburators as gas gugglers, and I was totally wrong by prejudice.

The Bravo II allows to use big efficient propellers, 3 and 4 blades, and that's perfect for working boats. Add the fact that the aluminum propellers are cheap (when I say cheap it's compared to other propellers), and if you hit something it won't break the transmission. Easy to repair the minor damages also.

Stern drives need great everyday care and maintenance. True also that escapes need to be surveyed.
On the work boats I counsel to change the engine and stern drive after 2000-2400 hours of use at 75% oh the power with good maintenance (the military way). It's cheaper in long term that trying to rebuild because the boat is stopped from working only 2 days and reliability is kept maximal with always new accesories. Losing a day work is very expensive, and more than expensive in high touristic season.

I like the engines kept well closed in a sound attenuating compartment easy to dry with a system of 2 pumps (the common plastic bilge pump are unreliable, forget them) and also easy to extinguish any fire with halogen or carbonic gas. I won't enter in the details of the gas engine compartment design.

So sinking the boat because of a joint problem is rather unlikely. I said once to a guy that beds were very dangerous places. The proof is that billions of human beings have died in a bed. Definitely not a good place to stay. He sleeps now on the floor.

 

I used to sell em fix em and race em soooo
I loved them

 

My OMC electric shift is 38 years old. I've owned it for 8 years. I replaced the ball gears once the first year I had it, they were worn and not aligned properly. I replace the water pump impeller every year, 2 hours work out of the water. Drain and flush the upper & lower gear gear housing, 1 hour. The steering arms, manual have given me the most fits because they were not installed correctly when the boat was retro-fitted with them, so if the outdrive pops up from hitting something, or if the rpms are too high in reverse, the arms bend from the torque of the outdrive rising so fast. I enlarged the bumper to stop this bending and have had no trouble since. I have resealed the upper and lower gear housing at every 300 hour mark, and the last time replaced the electric shift cable. Done the bellows twice just because. None of this was rocket science and is detailed and explained quite nicely in the oe service manual. That being said, if I didn't do all the work myself, I would face 3 issues. One, finding a trustworthy and competent mechanic to work on a unit that has been out of production since 1977, two, listening to him whine about hard to find parts, and three, the source of extra money needed to pay the exhorbitant bills he would come up with to do the work. I like the Electric Shift because of the smooth shift and quiet operation vs. the aphla one. The bellows is a p.i.t.a. to change but then so are spark plugs on my Windstar but I do that too, takes about the same amount of time. The boat I'm pushing is a 1971 Winner 23ft sport fisher, very very heavy. I tossed the original Kaiser V6, way to wimpy, and custom built a 4.3 and matched it to a OMC 800 intermediate housing with the hydraulic trim cylinders attached to the stringers. This set up allows me to cruise along at about 25-30 at 4000 rpm all day long if I choose to do so. The boat planes at about 3000 so that is where I usually keep it. It lives in Long Island Sound from April to November so the last reseal I had a buddy powder coat the housing and use the white anti-fouling paint for appearances. I get it from Jamestown Distributors and with a weekly brushing keeps the butt end looking all pretty and white, much to the consternation of the black anchor crowd(Mercruiser) and the local marina naysayers who hate anything that isn't the same as theirs.

 

Hmmm, I think these last few posts say it all. Bellows don't sink boats...lack of maintenance sinks boats. We could say the same thing for your cars or trucks. If you don't take care of them, they end up either in the shop or in the junkyard.

 

fasteddy106
You forgot to tell everyone how good the steering is on one of those, 90 degrees and the lower unit rotates around the top box...brilliant
no torque at all...

 

edjunior
My customers that set out to spend as much as they could on maintanence always ended up spending less than the penny pinchers..
I learnt one of lifes lessons as an appentice.
Rich people are rich because they spend their money better than poor people.
i.e they only buy a product once because they buy quality.

 

Merc Alpha One leaking due to damaged bellow

We just put our boat in the water last Saturday and it started leaking like crazy, I would say about a gallon a minute or more. Exaust bellow appears to be busted, also engine produces a lot of smoke that comes from outside the boat and from the bildge. Mechanic says he has to take the engine out to do a proper fix. Why should the engine be taking out? Also is it possible for merc to leak like that only due to busted bellow, or there's a bigger problem? It looked like with pump off our Sea Ray 27 would sink in a matter of hours.

 

Sounds like a cracked exhaust manifold. Was it pumping water from the engine into the bilge? I just repaired mine, cracked from a little bit of water and our -20 winter, at least I will find out when I put it in my dunk tank to test it. As far as do bellows sink boats. Yes, if you are in water you dont know, its dark, its the 4th of july and you might have had one to many barley pops and hit a rock that slams your lower unit up and rips the bellows off of its clamp. Then the guy farthest aft in the boat says " Hey, why are my feet getting wet". Then you have to make a bee-line for shore and run it aground. Not that it ever happened to me....

 

:You are right about the steering, very helpful in close quarters and backing into the slip, I can crabwalk mine right up to the gas dock with little effort. It also helps that I have the engine running so well that I can bring the idle down to 500rpm in gear without stalling. Cuts down on playing thump and bump with the dock, and helps with holding position waiting for the bridge to open in Niantic. Too bad they couldn't beef up that upper gear box to sustain the torque from the V8's or they would probably still be in business although you can buy a brand new electric shift from a Canadian mftg.

 

Sounds like a better job needs to be done before the boat is put up for the winter season and a more thorough inspection before it splashes in the spring. Pulling the motor will probably find some other issues that have been overlooked so it is not a bad idea though I believe it is necessary to do your job. It's been a while since I looked at my brothers Searay with the Merc set up so I can't remember exactly but if you have a service manual you can look at the exploded views to determine what your mechanic is referring to. Unless you can do the work yourself you don't have a very good arguing positon anyhow, so if you don't trust your mechanic you are in a bit of a pickle.

 

2farnorth,

Wow lucky "Not that it ever happened to me...." eh.......

Just a friend you know ......

 

Hey Landlubber, Yeah it was quite the scare, but I was able to tow it to a friends dock with about a third of the boat underwater. We put a battery charger on it and the pump was able to bail the water and then keep up with it. Then I went and got my truck and went to the other side of the river to the landing. My friend picked me up at the landing and we went back to my boat, started her up and went full board to the landing (about a half mile)where another guy backed my trailer in and I went straight up on it. No tears in the bellows, it just got knocked out of the big clamp that holds it on. The boat is a 1973 Larson runabout with a 165 HP OMC I/O. It was a closed bow but I cut the top of the bow out and built a platform and turned it into a center console. Then this winter I covered all the 'glass above the gunwhales with nice wood strips and stained it mahogoney with a clear coat of poly. Real mahogoney with an epoxy coat would be the right way to do it but it isnt a show boat, just something to get us out on the water during our extremely short summers.

 

Mahogony, Mahagony????