MAN D2840LE401

The engines you're looking at are the very last version of the 100% mechanical V10 in MAN lineup, capable of 820hp at 2300rpm.
It has been a very popular builders' choice for many years, when the V8 was only capable of 680hp, which was not enough for some boats that, on the other hand, didn't need the 1000+ of the V12.
They are widely regarded as solid and reliable, with the added bonus of not requiring any electronic wizard mechanic to fix anything.

They only began to be not attractive anymore when the V8 was spiced up to 800hp in the early noughties, offering a bit better power to weight ratio and also some space saving in the e/r.
In fact, that triggered a power increase also in the V10, initially to 1050hp (LE403), which was MAN's first attempt to introduce an electronic governor, with somewhat patchy results.
And eventually, they introduced the 1100hp (LE423), fully electronic and with common rail injection.
But both only lasted a few years, because eventually they phased out the V10 block altogether, since in the meantime the common rail V8 and V12 covered all the power nodes from 900 to 2000hp.

Bottom line, of all the MAN V10s, in terms of reliability I'd pick the LE401 anytime, assuming that their power is adequate for the boat size/type.
And also the 2600 hours per se wouldn't worry me too much, but it's reasonable to expect some serious maintenance to have been done, throughout their life.
What sort of service history have you been able to check?

I think we have the electronic/common rail V-8 "little brother" to those -- D2848LE423. AKA V8-900 CRM. So far, so good. It was expensive to bring the engines back into schedule according to MAN's recommended service regime (given the PO's neglect), but much of that came out of purchase price negotiations in our case. Routine service since then seems pretty much like any other 15L after-cooled turbo-charged diesel.

I would mention one thing that has been slightly surprising for me. I knew to expect wider engines, and that it would impact engine room space and mobility. I didn't appreciate how much, though. We have a 16' beam and I still have to duck and weave -- and sometimes squeeze -- to make my way through the engine room. Everywhere I want to be or go... there's a hose or cooler in the way. A foot wider beam would go a long way toward mitigating that.

I suspect the newer I6-800 -- or I6-850 -- might be about the perfect engine for our boat, assuming length could work. Cat's meow. Woulda been nice if that had existed when ours was built...

Two I know of. Hild's Marine Service, two sites, one near Annapolis somewhere (Broadneck or some such) and the other in Ocean City. Will Hild has apparently been around in MAN service the longest in the area.
My (brief) experience with Ben Hild (Will's son) has been very good, so far. Haven't done any hugely significant work, though, since we got the boat up from Florida (where Gulf Coast Diesel did the re-hab work).

The other near here is Shore Power, from Kent Island. Don't know more about them, but I've seen their work trucks in various places.

Performance Diesel in Texas (distributor, parts supplier, etc.) may show some others around here...

-Chris

I can imagine.

I just started an engine oil change, which will end up spanning several days. Yesterday was the "heat the engines (boat ride), take samples, drain the engines" phase. And that included taking the 5-gallon buckets to the recycling barrels here in the boatyard. (Approx 18 gallons, total.)

Couldn't loosen the oil filter drain plugs... and it was hot down there, got tired of arguing with 'em... so that's today... hopefully... even though the engines have cooled down. If I can get that sorted, tomorrow could be the "refill" day.

I'm stiff and sore... and there's something in the way, no matter where I want to be...

-Chris

Yeah, working on filters today. And sure enough I can't budge the drain plugs yet. Turns out I see I don't have a 17mm socket for the 1/2" drive; need a trip to the store, probably. The battery-powered socket thing might work, eventually. In the meantime, I've doused with Kroil and I have the butane torch handy.

Hadn't thought of doing filters first; good idea, thanks for that tip.

Last time I changed these filters, two plugs came out as normal, two came out with the adapters. PITA. As advised, I re-inserted the adapters using high-temp thread locker.. can't say yet whether that will have worked or not.

Aside from not being able to make much progress just this minute... the whole design doesn't seem to onerous to me. Spin-ons, right side up might be slightly more common, but they wouldn't self-drain. Spin-ons upside down could be a mess, unless there were drain plugs too. But then that'd be similar to what we've got, so maybe not much difference really.

I was eventually able to discover that MAN approves Rotella T6 under it's offshore name, Rumina or something like that. But the Delvac is what's in there right now.

-Chris

Well, turns out I did find a 17mm socket for a 1/2" drive... but it's a 12-point so not great.

Had to make a trip to bring the oil over, and the torque wrench... so I found and reviewed advice from Wendell (GCD) from my last (first) filter change. He suggested tapping the plug, and/or tightening it, first before trying to loosen. Says that can compress the crush washer and thereby loosen the plug. Sounds nifty to me. We'll see.

He also said the plugs and canister bolts want a minimum of 50 Newton-meters torque; guess I must have gotten that right.

Your MAN folks were probably following the best written direction they had available, hence the Delvac preference. Our MAN manual only listed two approved oils, both Mobil Delvac: 1 SHC 5w40, and XHP Extra 10w40. Never found either available, apparently because at least one had been superceded by Delvac 1 ESP 5w40 -- and that's what GCD used. That's also what Hild's uses; Ben was telling me they buy it in quantity.

More recently (but still probably during Covid shortages), while shopping for (and not easily finding) the Delvac, I found a 2009 MAN document with approved engine oils for their various specs. Shell Rimula R6 M 10w40 (sold overseas) seems closest to Rotella T6 5w40 that we have available here. And I was actually able to find some of that. I've just been holding that for this iin-progress (sorta) oil/filter change. The list actually includes some other possible lube oils that might be available in the US -- Castrol, for example -- but I haven't looked further at that.

-Chris

If you ever came across any written MAN recommendation for a specific brand/type of oil, I'd be interested to see it.
In fact, in my experience some MAN dealers recommend one or another brand (mostly Shell or Mobil around here, but not only), I suspect based just on what they find at cheaper drum prices.

All I'm aware of is that the official factory standard is either M3275 or M3277, for pre-common rail or common rail engines respectively (see attached "Approval Codes" abstract).
So, for your common rail engines, any M3277 compliant oil should be fine.

Now, I'm not sure of what brands are or aren't available in the US, but the latest MAN list of M3277 approved oils that I'm aware of is 7 pages long...!
I'm also attaching it for your reference.

PS: FWIW, I also use the Delvac for my non-CR engines, but the MX which is less expensive than the synthetic, while being still M3275 compliant (not M3277, though).

Thanks. I didn't mean MAN recommendation, just meant their "approval" for a given standard. 3277 in our case.

Despite the "2022" filename I gave it when I downloaded it, the attached 2015 MAN doc is an example of that I found. Several pages for each standard, and several standards included. Looks like the same basic info as in the docs you added.

Most of the brands mentioned are not sold here... at least under those names. Shell Rimula, for example, is called Rotella here... and there may be other similar instances that I just didn't recognize.

The only two from the lists that I found available here are the Mobil and the Shell (by the "U.S." name).

-Chris

And it turns out TAP TAP TAP worked like a champ.

-Chris