MAN 1200hp engines

I sold a 2001 Baia 63 Azzurra with the similar 1300hp but at 2300 hours, same 2.2 litre engine block.
They where rebuilt at around 2000 hours in this case, in a more difficult environment cause of surface drives.
Make an oil analysis to know where they stand at.
I think if you keep them at a correct load (difficult to know with old engines) but at 70% rpm of under 2000 and around 1900 they should give over 2000 engine hours without a rebuild.
You have Mans valve checking and injector cleaning but that is at 1000 hours, and if you rest her in Winter every four to five seasons I would suggest a good cleaning system clean, most important the heat exchangers.

That was the LE404 engine, not the LE406.
Indeed based on the same block - BTW, 22 litres obviously, not 2.2! - but that's where similarities end.
The 1200hp LE406 was in fact the very last development of their fully mechanical engines, produced for decades and widely regarded as very reliable.
The 1300hp LE404 was instead among the very first engines where MAN adopted an electronic governor (so-called "EDC"), a technology which wasn't exempt from teething troubles and was phased out just a few years later, when they jumped on the common rail bandwagon.

If given a choice, I'd have the LE406 rather than the slightly more powerful LE404 anytime.
Which doesn't mean the LE406 can last forever, though.
I mean, pretty sure the reason why on that Baia the engines were rebuilt as early as 2000 hours has much more to see with the typical usage of those boats, whose owners most often than not see the throttle as an on-off switch (either idle or WOT!).
But in a Viking 60' cruiser, they probably had a much easier life, and I wouldn't be surprised if they would be good for another thousand hours or two, before needing a rebuild...

@Bill, ref your last question on the cost difference, I don't think it's possible give you any reasonable number.
But brands aside, you should consider that the MANs you are comparing with your current Cummins are more than twice the displacement, twice the power, twice the cylinders/valves/turbos. And 10 years older.
So, aside from the regular stuff like oil and filters, whose difference is unlikely to break the bank (also because MANs hold a little oil quantity in proportion to their size) for all the rest I think it's only fair to expect to double also the maintenance costs...

Gulf Coast Diesel in Punta Gorda brought our MANs back into service schedule compliance when we got the boat in June 2021. And then they also corrected the additional survey-discovered problems at the same time. My impression, they did a great job, and IIRC their advance estimate was within about $1K of eventual actual. Wendel has retired since then, and I understand our lead tech has branched out somewhere... so dunno how changes in the meantime may have affected the situation...

Reading has suggested to me that MAN maintenance costs are similar to maintenance costs of other engines of the same size. Arm and a leg -- maybe add a mule and good hunting dog -- for large engines, but brand doesn't seem to matter much. Some of the Cats (3196s, C12s, I think) in boats we looked at had been equally neglected, and Cat's guidance to "replace the heat exchangers every time you turn around" seems to be a major cost factor for those.

-Chris

If given a choice between a 1996 MAN and a same vintage Cat 3412, I also would rather pick the latter.
But I'm not so sure if you would compare MANs with similar Cats built after they started designing and building CACs and HEs as if they were disposable items - and potentially engine wrecking ones at that!

Are they giving away those chinese aftercoolers, in the US?
Around here they are as expensive as if they were still properly built, if not more.
And together also with just about all other bits, make Cat maintenance a nightmare, compared not only to MANs (which are expensive), but also MTUs (which are more expensive than MANs).
That aside, what price do you give to peace of mind?
I'm of course happy for you if your C32s never blew out, but some did!

If that's the boat, she ain't what I figured when I said the engines probably had an easy life in a "cruiser".
Which doesn't imply they are shot and in need of immediate rebuild, of course.
Quite the opposite in fact, judging from the pics alone which show a remarkably clean e/r, and even more so considering the boat age and hours clocked. Christ, even the chromed valve covers (which usually look bad shortly after the boat is built!) seem in decent condition.
Also the fact that the large cover/protection on the belts is still in place suggests that whoever took care of maintenance was very careful.
I mean, in my boat I got rid of them shortly after I bought her, just for accessibility convenience, but no serious mechanic would do that, because of the risk involved for anyone entering the e/r with the engines running and the pulleys/belts spinning.

As an aside, @Verdegirl910: if the boat you are considering is indeed the one linked by CR, and if you will go see her, I would be curious to hear what the bit that I circled in red is. Or also from anyone else who might know, of course.
Me, I've never seen that thing on any MANs, and I've seen quite a few - both older and newer.

Murphy liquid level gauge