With Banks and Buck coming out with 550-700hp marine diesels, boatbuyers will finally have modern, high-performance diesel engines to choose from;

www.buckdiesel.com

I heard rumors that Merc is coming out with a ~600+ HP that will bolt onto a NXT drive

I wonder how much those diesels weigh- they don't mention it on their website. I bet they are heavy.

I think Raylar has a 550HP smallblock that weighs 550lbs- now that's a great motor!!! (there was a recent add in Powerboat Mag about these motors)

Hot Knots,

Don't want to rain on you, but that Buck engine is a dream and so is that website. It hasn't changed in months and the only pic of an engine on a dyno isn't even a Buck!!! 2008 odel year is over so they pretty much missed their launch.

If they build them, they will be great work boat engines, they have many great ideas for a trawler engine but performance engines - never!!!!

Joe Gere

The engine on the dyno is a not a Buck engine? Why would he put a picture on his site of a motor that is not his??

Merc's diesel line is now handled by CMD Marine. That stands for Cummins Mercruiser Diesel. Cummins has the QSC8.3L available @ 600 hp. But it's too heavy for outdrive usage. The smaller QSB5.9L is available at up to 480hp. Cummins has been working towards turning that engine up to 600hp and thats the one everyone is waiting for...and waiting...and waiting...and waiting. What you need to know is 600 hp of diesel and 600 hp of gasoline are two totally different animals. The NXT drive is a lightweight version of the good ole #6 drive. The NXT drive is rated to 700 hp @ 800 ftlbs of torque. Now a QSB5.9L set at 330 hp is rated at 830 ftlbs of torque. At 480 hp its rated at 940 ftlbs of torque. If they ever get it cranked up to 600 hp its gonna be over 1000 ftbls of torque. The only drive that Mercruiser has that could handle that is the venerable #6 Drive which is rated to 1160 ftlbs of torgue. It's not a rumor it's a myth that has been busted...

Hot Knots,

I don't why they would put one there that is not there's but,
here's how I know. Look at the Buck pics of castings, they have a 1 peice lower end where the crank mounts with individual cylinders and heads bolted to it - like a radial aircraft engine or a Harley Davidson. I must say, I like the concept, not knocking their idea, I think maintenance wise very cool!

Look at the engine on the dyno and the upper and lower block (crank & cylinder area) are all one peice like a Cummins, Yanmar etc. Also, why put an old ratty painted blue engine up there when you have all these need unpainted engines. No one with any amount of engine design/building experience would paint a new/revolutionary engine and then throw it on the dyno. It's an old marine engine they used to test their dyno, that's my guess.

Again, I like the concept, but structually I doubt it will last as a performance engine which implies it needs to be high rpm and high hp.

Joe Gere

They may be behind schedule, but I do believe there is a real company working on something there. I "ran into" an engineer who worked for them on a car website a few months back, and he didn't claim to be the owner or whatever as I'd expect from something that was really a "dream" and 1-man show. We'll see if something ever really comes of it though.

I don't doubt they are building something, I think it's a dream to call it "high-performance diesel engines". I could be wrong but putting them in a context with Banks would imply they are geared toward the "Go fast" boats

Look at the bell housing they're using an SAE #2. If they were performance based they would use a #3, the dia of a #2 alone makes very hard to mount engines side by side. The weight of the larger #2 housing along with the weight of the flywheel all says it a pleasure craft engine. You would not want to spin an SAE #2 flywheel real fast, it's too big.

Again, just my experience has taught me that, nothing else.

Also, please I like what they are doing, it's great, but not a substitute for 525 or 700 Merc's. They are not claiming to be a High Peformance engine company. They have showed up here on OSO a few times being championed by people who feel the need to say they are "high Peformance" and imply they are for the "go fast" crowd.

I don't pretend to know anything about this subject but don't diesels operate at lower RPM's anyway? If that is true are you spinning a "bigger" prop to compensate for lower RPM's or does the transmission increase the rpm to the Prop?