MTU vs CAT

[Regal2800]

im looking at an early-mid 2000s 65 hatteras. i noticed some come with a lower HP Cat 3412 and others come with the MTU 16v2000. The MTU boats get up to about 40 knots and the cats low 30s. Does anyone know how much more expensive the MTU will be to maintain/rebuild? I understand that MTU is a german company, but they also own detroit diesels which aren't overly expensive to maintain so im looking for first hand knowledge in comparing MTU vs. Cat. Thanks.

[car54]

I wouldnt recommend all cats over mtu, but the 3412 is a simple, stout engine with a long history. The 16v2000 is four more cylinders and also reliable compared to some other mtus, but will probably cost a lot more to repair when stuff goes wrong.

[miboatnutz]

I would get the manufacturers preventative maintenance schedules for both engines and compare the two. From a stray comment or two on this forum there may be a major service interval for the MTU's every two thousand hours or so.

Other thing I'd do is solicit comments regarding both engines from people on Boatdiesel.com. Pretty diverse range of diesel boat owners on that site.

[jim rosenthal]

My CAT dealer friends say taht the 3412 is one of the best engines CAT ever made. Although you wouldn't get as much speed, your maintenance costs are likely to be less with CATs.

[Pascal]

I used to run a 70’ MY (not a hatt) with pair of 2003 3412Es (1400hp). They had about 1400 hours when I got on the boat and 8 years later it sold with 5400. Passed survey and oil analysis with flying colors. In 4000 we did a couple of $5000 (both engines) services, replaced one fuel cooler, one starter And not much more. Even impellers lasted a couple of years

No experience with the MTUs but I would not assume that because MTU owns Detroit maintenance will be cheap. I think they will be closer to MAN . Good suggestion above to look at the service requirements and get some numbers from an MTU dealer

I would also look at ER space with the bigger MTUs. Bigger engines means less space not only around the engines but also gens, air cons etc. and even though Hatteras designs the best ERs, it can still be an issue b

[Cricket]

Think 3412 @ 1400hp was the first 3412's with raw water cooled after coolers. Either 1300hp or possibly 1350hp was the last freshwater cooled after/inter cooled engines. CAT now has a service life for seawater cooled after coolers, think lifespan is 5 years to replace.
I'm a CAT guy but they're both very good engines, would be hard for me to turn down the extra speed......

[dottieshusband]

One thing I like about MTU's is they have individual cylinder heads.. not a deal breaker on other engines, and I've never heard anything negative about them. As others have said, the 3412 is a gold standard engine.

[SKYCHENEY]

I once read an article listing the best diesel engines ever built. The 16v2000 was on that list. That said, I know the 3412's have a great reputation as well.

Since both are good engines, it may be other things about each boat that may influence your decision.

[rourkeh]

If you are concerned about maintenance cost the Cat is going to be less expensive.
MTU service schedule is more rigorous, and parts are very expensive compared to CAT ( owned by Rolls Royce)
How important is the ability to run at or near 40 knots. How often would you really do that?
I would get the fuel burn curves for both engines and look at how your intended usage is impacted by fuel consumption which is a much bigger cost of ownership than maintenance.
Both engines have a long history of reliability so it really comes down to personal preference.
For my money the Cats are as close to bullet proof as you will find if they were well taken care of and you continue to do so.

[Pascal]

One thing I forgot to mention in my early reply is the engine management. From around 2000 Cats had a very good electronic display which showed any error in plain English.

My only experience with MTUs was running another 84 lazzara for a few days but an 2008 with MTUs for a few days. The boat didn’t have any digital displays at the helm, only an alarm light. The you had to go into the ER to read an error code...I forgot which MTUs it had, they were around 1500hp. Made troubleshooting a real PITA