Tickin Time Bombs?

[jim rosenthal]

I agree that the GM 6.5 and 8.2 diesels were a worthy successor to their Toroflows- just knowing about those miserable engines dates me, doesn't it? The 6.5, especially, and 8.2 were POSs.

As I pointed out, service and owner care are the keys to the entire equation. I think of the lives of diesels between overhauls as related to how much fuel goes through them- my understanding is that fleet operators service truck engines based on hours of operation and how much fuel they've used. Fuel usage corresponds to how much work you're asking the engines to do, right? And how much you're asking them to do equates to how long they will run between overhauls.

So, if you have 6-71 TIBs, rated at 485 hp per side (about a horse per cubic inch, incidentally- 6-71s must be the world's heaviest 426s lol) but you run them at cruise, not making their full rated power, you'll get a long time out of them. Especially if you are conscientious about oil changes, cooling, keeping them clean inside and out, and making sure they are propped right as you little by little load your boat up with all the stuff that inevitably finds its way onto a boat.

I like the later 38 Hatteras convertible- they are nicely laid out boats, and this one seems affordable based on the asking price. I DO believe in engine surveys, providing you don't get an unqualified surveyor. That's why I mentioned Tom Hugg, who is the local go-to guy on DDs.

Of course, the figure of 485 hp DOES make you think about C-series Cummins remans, now, doesn't it.... they weigh less and use less fuel.

See- here we go....

As far as them being the only diesel out there, well, they weren't- there were Cummins diesels, and also Cats- but I agree that for a long time the most common marine diesels were DDs. That period lasted too long, really- the engines are too heavy and they are noisy and don't make enough power for their weight. But when you're talking about a boat built in the 80s or 90s, in which you don't want to invest in new engines, you accept what they have, and you could do far worse than 6-71TIBs.

Volvos, for example.

 

[racclarkson@gmail.com]

Or maybe they have an appreciation for modern, clean burning, 4 stroke, direct injected common rail diesel technology. Just saying. But simplicity and mechanical injection does have its benefits.

If you have an appreciation for modern, clean burning, 4 stroke, direct injected common rail technology then a deep love of $10,000 thousand hour checks (that's $20,000 for most everyone) and all the other stuff that goes with it is helpful. I know it's just an opinion, but it was easier for me to justify spending that kind of dough on something that produced the income to pay that bill. So yeah it's a stone-aged engine, but even a caveman can work on it...or at least save you 15% on car insurance.
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[MVCaprice]

I have seen boats with modern diesels get towed in because a relay or some $50 electrical part failed.

This is a very real scenario. If something as simple as a map sensor goes bad and not only do you have a motor that doesn't work, you may very well be dumping excessive fuel into the motor or other critical problems if for some reason the signal scaling on the motor doesn't trigger an alert. Granted likely limp mode will get triggered in these scenarios, but still! Also the likelihood of wiring based intermittent issues is always there and they are a real pain to find. There are entire categories of issues that don't exist on the Detroit.

It's worth mentioning that there are some scenarios where a common rail helps dramatically. Startup, extended low RPM cruising, fuel management etc. Are these worth a total repower on most of our boats probably not!

 

[MVCaprice]

then a deep love of $10,000 thousand hour checks (that's $20,000 for most everyone) and all the other stuff that goes with it is helpful.

Yes. Violent agreement. I am just daydreaming. What you pay for a boat with these is insane!

 

[luckydave215]

Dave where did you find 40 degrees in San Diego. I can confirm that Dave’s engines don’t even produce a puff of smoke on start up. John

Well, it's 46 in Encinitas right now, at 10;30 am.
Ok, that's really unusual but not unheard of, and starts at 0dark thirty in January can often be that cold.