MAN 820 or 1050 Motors?

Here's my comment. Call the local Man engine mechanic for that area and ask him your questions. Mine was more than willing to share some of Man issues.

We had a 66´boat with twin V10 820 hp and they were smokey at startup from cold, but not at restart and running. More vibrations than the V12, but otherwise reliable. Perhaps a bit heavy with todays standard for a fast boat...

Hi,

A diesel engine that smokes on startup and settles down when warm and doesn't smoke on restart can often be helped to stop the startup belch by the use of Jacket Water Heaters.

These are basically a thermostatically controlled immersion heater in a container , the water can either circulate by convection or some of them ( I am thinking of MTU here) have a small circulation pump similar to the central heating in your house.

K1W1

I have immersion heaters on my 820's and they do in fact eliminate smoke on start up. I think they come as a stock item. They are also useful in the winter to keep my engine room at about 45 even with 32 degree water under the boat

From what I have seen, when MAN engines are out of warranty most owners are doing the maintanence by engine hours, not by the MAN every 2 year requirement.

I've run both the 820's and 1050's in several different boats.

The 1050's do have some issues with sensors (coolant pressure sensor is one of them) and the actual alarm display was another I've seen. They do smoke a bit under 1000 rpms but wouldn't say it's horrible, and cold startup on a cold day can be embarassing. I have noticed a harmonics/vibration between both engines at lower rpm's with the 1050's that you feel in the boat. Some more than others. At higher speeds they run very good and are fuel efficient for the HP produced. I would take these over 12v92's or 12v183's in a heartbeat though.

I've also run several sets of the 820's and they run good, very little smoke if any on startup on the ones I've run, virtually no smoke at trolling speeds but still the funky smell.

And it was the MAN 820 hp V10, not the MAN 820 hp V8?

Most of the MAN's I have run are 1995 and newer. I believe they are the V8 ones, but haven't paid much attention and couldn't say for certain.

I do know that doing the 1000 hour valve adjustment and injectors every 500 hours benefits them greatly both in the smoke department and performance department.

I agree wholeheartedly with CaptJ on these points.

I ran a boat with a pair of V-12 1000hp MAN's, and we did valves, injectors, compression test, borescope annually. (About 450 hrs. per year on average)

On 2 separate occasions the compression test indicated concerns in a cylinder, it was easy to pull the individual head, and service the head and in one instance replace the piston and liner well before things got serious.

An injector going bad can very quickly have a negative effect on that cylinder, we figured the extra preventative maintenance was well worth the extra expense and effort, as opposed to waiting for problems to manifest themselves.

The boat has since been repowered with common rail MAN's, and now a computer diagnostic has taken the place of all those measures.

The 1,000 hour service through the MAN dealer for a pair of 820's was around $16k for both engines, the 1050's were more. If I remember right.

what do they do at 1000 hours that costs $16k?

Remove all of the heat exchangers, change all injectors, adjust valves, standard servicing- oil/filters, fuel filters etc...... Keep in Mind that you're paying the $1.50 exchange rate on all MAN parts, and with the individual heads there is more labor and parts (gaskets, etc) to adjust the valves. Also I believe one of the heat exchangers is in the valley and a lot of labor to remove if I remember.

My 820's are V10's. Both my 400 and 1000 service were about $16k. Heat exchangers, injectors, valves adjustments as described above. Ill go back to my invoice to look for other work. Did they do something with the turbos??
I'll check.

And then some! The parts are pricey. The service is called for every 2 years OR 1000 hours. Most people do the first 2 yr service to stay in warranty for extended warrianties and such, and then do it every 1000 hours.

Like Capt J says, MAN has a crazy schedule to stay in warranty. Injectors every 200 for my 820s. But once we MAN owners are on our own, most of us go to the "cat" schedule without incident. The price of parts is still crippling, though.

Just looked at my invoices, on my 1000 hour service, aside from the work described by Capt J., they disasembled and sent out all the heat exchangers, the intercoolers, and 4 turbos for cleaning. But still expensive. On my job, they also had to replace an oil pan gasket in place, and changed all the fluids including coolant.

And I lied about my 400 hour service. That was $6K- Two mechanics traveled to my boat from Mystic Ct (hundred? miles) re-torqued heads and replaced injectors, etc