Mtu 4000 M-90 Break-in

Hi Saar & welcome to YF,
At 150 hrs your 4000 series are already broken in so to speak. A new MTU 4 stroke engine break In for the first 50 hrs you would want to have varying RPM , loading for the head temps & exhaust temps to seat the valves and seats properly. Basically MTU
Will tell you not to run the same RPM for extended periods of time for a proper break in period. MTU will also ask that you don't let the new engine idle for long periods of time While in the break in period. This pretty much would apply to any new engine be it 2 stroke diesel , gasoline engine or a gas turbine. You want expansion and contraction to take place within the different load heat specs that the engine was designed to operate.

MTU has a good online presence. Google your MTU model number for operation and maintenance files and you'll find PDF's with complete manuals and attachments. You might have to drill down a couple of times to get past the spec sheets but the complete manuals are out there.

Saar,
The best thing that you can do if your serious about learning how to maintain and have an above average working knowledge of this engine is to take the MTU CM2 maintainers course for the 4000 series from the MTU training centers. I took a 4000 series course in 2006 in Ft Lauderdale but I think the training is now done in Detroit MI.
Go to Mtu-online.com and have a look see for the courses offered. If your vessel travels to the Med. than I recommend the course syllabus at the Plant 1 factory in Friedrickchafen Germany. Try to stay in a hotel in Romanshorn Switzerland and take the ferry across lake Constance to Friedrichshafen in the morning and afternoon. You'll make a lifetime memory doing this. Spectacularly beautiful. I was lucky enough to spend eight weeks there taking the 396 and 595 technicians courses and will be ever grateful to my employer
Subaru of America for sending the second engineer and myself there.