Stern Drives and Salt Water

Let's talk before recent market events first. Stern drives were always more an inland propulsion system than ocean. The older stern drives were very poor for salt water. In more recent years, the stern drive manufacturers did design systems for salt water, Seacore by Mercruiser and Ocean-X by Volvo. If the stern drive had one of those systems then it would be ok for salt water, still not as desirable as inboard but much less expensive too. Now, any stern drive ever used in salt water is the impossible to sell to fresh water buyers so that means if you're buying, perhaps a great deal but if you're selling, extremely difficult.

Then there are recent market events. The growth of outboards and the demise of stern drives. Stern drives once were the flashy and desirable way to go on inland lakes. All 5 of the lake boats I owned from 1983 to 2012 were stern drives. Outboards during those days were the cheap route but everyone wanted stern drives. However, that has changed. The passion of the consumer for stern drives has died, even for what was their primary use. Inboards moved in with all the ski and wake boats. Now outboards have moved up. Sales of stern drives just keep declining.

So, if you see Seacore or Ocean-X and they check out and survey well and you just want to buy to use but don't care what they bring on a resell ever then go for it. Otherwise, I wouldn't recommend it.

My first boat back in the 80s had a single Volvo V8 with 280 sterndrive upgraded after a few years to a duo prop lower unit. I had the boat in water year round, first in st Barths for 9 years then in Miami for a few more. Never had a corrosion issue. And it was raw water cooled...

I think Merc gave stern drives a bad reputation...

That said I also believe that stern drives are done and 4 stroke Yamaha Outboards are the way to go

Salt water is hard on everything. Saline content rises as your latitude lowers. If you leave the drive in the water, corrosion is the least of your problems...

The lake I grew up on was nearly as bad as coastal waters due to a high mineral content of the water which came out of the mountains. Each lake higher on the river was even worse. So hull cleaning and outdrive cleaning were a regular part of life there too.

There was a joke I first heard from a Mercury dealer and it applied to Mercury outboards and Mercruiser when I was young. It was, "What's the number one tool of a Mercury mechanic?" The answer was "A crowbar." The reason was that was the only way to typically remove a lower unit as they would "weld" to the upper section. The Mercury dealer basically had a disclaimer that there was a risk of cracking the lower housing in doing so and, if that did happen, it was at the owner's expense to replace it. Fortunately, today's units are not as bad, but the problem does still exist to a degree.

I've seen lower units that looked almost as bad as the one in Carl's photo on the lake, boats that had been neglected and left in the water for years.

Having spent the last 20 years working with both Merc and Volvo outdrives, would I ever own one?
No.

Do they have a place in the marine market?
Yes. In certain uses, they deliver really well for their price compared to other options. A yearly service and clean is normal for a drive that is in use regularly.

The newer ones have much better corrosion protection, ceramic coatings and such, than the old types. Don't skimp on servicing , using crappy oils or bolting on cheap Chinese anodes that do nothing. Like anything in the marine world, give it care and it will care for you.

Used stern drives on my sportboats in the upper Great Lakes for years. Never had any problems whatsoever. Took one to west coast Florida for a work related vacation. About two months later the outdrive was all but shot. Your question just reminded me as to how salty the water was below 25S latitude. We don't have that problem at 55N - just icebergs.

Let me say this again. 15 years in salt water, never had to use a crowbar and never had corrosion issues.

I think the older ones were much better than when the beam counters started having a voice with lesser alloys.

Would i own one again? No... because of how modern 4 strokes outboards have improved.

Well... I d probably take my old raw water cooled Volvo with 280 DP over a Mercury 4 strokes any day...

The Volvos were much better than the Mercruisers when it came to salt water.

My point... generalizations are rarely accurate.

I always felt that Volvo drives did better in salt water. In the 70s, had 270 drive. Except for that dam reverse latch, is was a bomb proof drive.
Unlike S/E FL were you can spit in the gulf stream from the beach, in N/E FL, it's off shore a ways.
So many miles, so many hours. not an issue with that drive till it was sold.

During the 80s, In Savannah GA, I restored old Vega 20s.
Volvo 100b drives. Kind of the model 1.
That case alloy seemed to be in good shape also.

So, my question; Did Volvo/Penta use a better alloy in their cases?

Apparently, in those dark, distant days we had things called engineers and craftsmen. They were free to create machines that had no involvement from accountants. They simply worked and could be repaired without special tools.

Volvo still does a better job on outdrives than Mercruiser, when it comes to protection.

One of my stern drive was a 60hp Mercruiser diesel. Cool at the time, built in 1965-68 - exc for engine parts. The engine was Renault.

Merc also used the 2.25ltr Landrover diesel in the mid 60's.

https://books.google.gg/books?id=QeMDAAAAMBAJ&pg=PA24&lpg=PA24&dq=mercruiser+rover+diesel&source=bl&ots=p-MxI9j7V9&sig=wS_XBw-iy3jU-TxkeSekr0c842E&hl=en&sa=X&ved=2ahUKEwiEsZmJj8DcAhWnyIUKHYZEAyYQ6AEwAHoECAEQAQ#v=onepage&q=mercruiser rover diesel&f=false

I bought mine in Amsterdam.

Engineers used to control companies, now finance/accountants have taken over.
Now the usual mantra is - how can you save me 5% this year?

I have witnessed this in my other career. Bean counters started making more money than the folks doing the work. Justified their jobs on the money saved and continued to squeeze that onion till nothing was left, company fails and the big owners wonder what happened.
It always amaze me that the big owners long forgot it's the customer and the bottom few of the company is what matters.
If Brunswick wanted to keep a good drive case in the water, they easily could.

But then, they could not sell you a new case a few years later....