MAN 800HP engines

The hp to weight is great. When they run, It's great. Fuel economy is very good. It's down hill after that. If your looking at a purchase, find your mechanic now. Find every service record. Get that extensive engine survey and purchase the extended warranty if it's available..
I've run a few and worked on them when I have to. I like them myself when there is room around them. Parts are very expensive and a good MAN mechanic is hard to fine (and expensive). I would take them over a MTU setup if I had a choice.
Keep us up on what you find.
,rc

Not may MTU options at 800 hp, are you thinking about the 825hp MTU/Detroit Diesel Series 60?

Either that or 8v183's.

I've run several sets of the 820's. I know one boat where they're pushing around 5500 hours and still running good. I just ran another yacht with 2600 hours on them and they ran good as well. As far as I know the 820 MAN's are durable. Parts are typical MAN prices, but the engine tend to run good and are ok on fuel usage.....I think a set burns 60 gph at cruise if I remember right.

I did not mean to bash the Detroit blocks. I was poorly comparing my general feelings about MAN vs. others.

There may be a recommended service around 800 to 900 hours, has this been done yet?

Comparing an out of production, legacy Series 183 with a relatively obscure population of 8V's to a highly produced/commonly available MAN engine is stretching it quite a bit, don't you think?

I love the comment about "I know one boat owner where there pushing around 5500 hours"..... This says nothing about the way the owner operated the vessel and what level of maintenance occurs. Every engine builder has a outstanding example of longevity, usually with a meticulous owner who is aware of how hard to push a vessel.

Getting back to the topic, where the C12's available in 1998 - 2004? I am not sure, but the CAT offerings may have been different at the time of production?

Get a copy of the maintenance schedule for the MANs and CATs and get quotes for basic service at the set intervals then do the math

That a really the best way to compare costs

If you are buying any boat and have not done what Pascal suggests, you have not fone your due diligence to the right level.

The engine makers all have published maintenance schedules, typically based on an assumed Operational Load Profile, bounded by the estimated Time Between Overhaul (TBO), either in amount of fuel burned or engine hours. It's accuracy depends on how well the running of your boat matches to the assumed Load Profile, which tends to be conservative in most (but not all) cases.

Maintenance is typically broken down as scheduled (oil changes, coolant, etc.) and preventative (raw water pumps, bigger components like cylinder heads or turbos) and relates to the overall philosophy of the engine make.

Take this Maintenance Schedule to your servicing distributor or techniician and have him quote all the maintenance events listed, and you will better understand what the cost of ownership is for your brand of engine.

For an active pleasure craft boater, let's say 500+ hours per year, fuel will typically be the larger annual expense. Below that, maintenance costs can be the prime driver for annual expenses.

I really am not following what you're getting at. Were you drunk when you posted this?

The comment was to your post of the Series 60 800hp and mentioning there are not many MTU's around in that horsepower range, I simply stated that MTU also made the 8v183's back then, and I was not comparing them to the MAN's.

Considering a small percentage of Man 820's in recreational yachts have seen more than 2000 hours, let alone a testament of someone owning a set with 5500 hours and that they're still running, is an accomplishment. Anyways, the 5500 hour boat is a 2001 50' SF that has fished A LOT of tournaments most of it's life. The boat runs at 1950rpms or trolling speeds. The 2600 hour boat was a 61 Viking SC that again ran mostly at 1950 rpm's and some idling. The Sportfish gets oil changes and this and that, but definately not the MAN service by the book. The Viking got it's 2000 hour service at 2400 hours if that tells you anything. These are examples of boats that I have run with these motors, not some docktalk from the marina across the way. I've found them to be durable.

Hey PacBlue, lighten up! you are relatively new here. Your first post to which CaptJ responded would have gotten you a punch to your nose in real life. We like info here not wise guys with "virtual" immunity. I have 820's with 2200 hours on them - and you can't catch me on the way out.

C series Caterpillars didn't start showing up on the scene until around 2004. The C18's and C30's were the earliest C series Cat's. 3196 Cat's were usually what was found back then either in a 660hp configeration or a rarer 800hp configuration. The 3196's had a lot of problems in the beginning with blown motors from faulty aftercoolers and such. With the updates they are a good motor and the motors around today should all have been updated.

Wow, first being called a drunk and now throwing in some physical violence for good measure, what a friendly group!

Since the original post was related to an 800hp, 8 cylinder MAN and a CAT C12, why bring in a 10 cylinder, 820hp, 18 liter MAN into the conversation? It is like saying to your boating buddy, hey what do you think of a CAT C12, and getting a reply back like "I know a guy with a CAT 3406 who's got 10,000 hours and its just great!" An apples and oranges thing, you know?

Never questioned the durability of an 820hp MAN.............

Cat C12's did not exist during the origional posters time period 1998-2004. The motors I was talking about are 8 cylinder MAN's.

Nose

A punch in the nose is nothing to what I was promised on another thread.

Anyway, I would ask what kind of boat the engines are in as some of the 800's were in boats that needed more power and in turn worked harder (high load even at cruising)

I agree, in my experience the MAN 800's don't produce as much torque as the CAT's in this HP range, and they tend to do really well in boats that cruise at 24 knots +, since in rougher seas they don't get as loaded up climbing waves and such. The post cruised at 26-27 knots, and the Viking SC at 24 knots with them. Heavier boats that tend to cruise at 20 knots or less, seem to tend to fair better with motors with more torque....

Yes, they should be fine to run another 1000 hours without any major servicing except for your normal oil changes, fuel filters, impellors etc. They should be fine in that boat, just make sure it's propped so they achieve the correct RPM's at WOT. They should be good for 5,000 hours minimum, if taken care of. I personally feel you can do this service (cleaning of aftercoolers, heat exchangers, etc....on the hour side of the scale, and not the time side (every 2 years). Make sure the valve adjustment and injectors are done in that service.

Yes, the 3196's had major problems with the aftercoolers leaking. HOWEVER, CAT really stepped up to the plate and did rebuilds, 2 years, of extended warranty, updated aftercoolers for their customers on them. A friend of mine ran a 1996 3196 boat, that was 3 months out of the initial 2 year warranty, had 2100 hours, when 1 blew. CAT rebuilt both motors and updated them for free and threw in a 2 year warranty. They're good motors with the updates and very torquey. C12s came along sometime around 2007 I think.

I think I know the boat that you're talking about as I looked at it last year when I was in the market for a 58 predator. My advice to you would be to pass on this boat and find a 58 with 10 cylinder mans like I did. Btw, the 1000 hour service will cost a lot more than $25k if done right, I know as I'm just wrapping up that service on the 10's.