Looking to Purchase 1990's Hatteras Motor Yacht with Detroit's

I agree with these sentiments. I'm not a fan of the 92's and while the DDECs start and run good, they don't last nearly as long due to their HP output and being 92's. I haven't seen 92's make anymore HP than 71's after they get 500 hours on them.......not to mention most 92 owners run them around at 1800 rpms....so why even have larger engines. Yes, detroits are pigs......stinky exhaust, leak oil, a bit crude, a bit noisy, but they'll always pretty much run. If you run the Detroits at hull speed.....1000 rpms, they're a lot more fuel efficient than a 4 stroke diesel......up top at cruise, not so much.......If you want CATs, late 90's early 2000s had 3412s, a darn good motor.

I've run DDs for 50+ years and they are my favorite. I've been rebuilding my own engines since 1969. The 12v71 is more reliable and cheaper to overhaul than 92s. They are a mechanical engine that has no power requirements once started. There is no injector pump, no real bleeding of fuel. The basic 71 design has been around since the mid 1930s. Not only Detroit Diesel, but many other manufacturers make good replacement parts. All parts except big cast items are still being made. I believe the 471 (same sleeves, rings, pistons, and bearings) is still being made. 71s are used all over the world and in more applications than marine. Everthing on the engine pumps, etc., was designed to be rebuilt in the field. Good mechanics are best found in large ports or especially fishing ports. Also business that cater to oil fields. But there are many general marine mechanics, experienced in other brands, that think they know DDs. They are the source of many unhappy DD owners.
Nothing against other brands. Cat makes great engines, but parts are high. Cummings are also good engines. I would stay away from engines that are computer controlled. Besides the electronics, you have many sensors, miles of wiring and are hostage to the OEM. There isn't room or time for all the electronic horror stories I have seen or heard.
Ebay is a good source for spare pumps, etc.

The Cat C18's are the most bulletproof engine Cat has made in the last 10 years. They're a geat motor, run very well, and very few problems. I don't think the 61' is a very fast boat, but with the C18's should be faster than it was with the DD's. The beam will help with ride.

That would be a repowered boat, yes?

-Chris

I would be sprinting towards it. The C18's are GREAT motors and far superior in every aspect to the detroits.

Until you start paying for parts.

C18 parts are not that bad in price in all honesty. You're maintenance parts are comparable to detroits. The turbo's are actually cheaper because generally it's just the cartridge inside of them that needs to be replaced. I'd take a 9 year old engine over a 40 year old engine anyday. The C18's have a 10,000 hour service life.........

I love my 1271's and you'll hear pros and cons on both 71's and 92's. Best advice, listen to Ralph Crapps. IMHO Ralph is the expert on the subject.