Stery Engines in a 28 J/S

[Diesel]

Severn River Marine Services in Maryland recently repowered a 28 Jackshaft boat with a pair of Steyrs. Performance was reported at 31 kts at cruise 41 kts at WOT. Fuel burn of 5 gallons per hour each at cruise. Over 3 miles per gallon!!!

Does anyone know this boat/owner?

Diesel

[PurpleCedarPlug]

Very Interesting. Never heard of them. Looked at their website..

Hopefully someone will respond. I would also like to know more..

[Bluefin 32]

Not implausible as the Steyr is a 250hp ultralight common rail motor. They only weigh about 700lbs apiece so that means a pair would be only 1400 lbs versus 2450 for a pair of Volvo D4-260s. A 1000 pounds of weight out of the boat would do a lot for the speed. Since a straight inboard with D4s can cruise around 27kts, 31 kts for this setup with a sterndrive seems quite possible. The fuel burn number can't be right, however, as that implies a level of efficiency that no motor could achieve. You can't produce the requisite horsepower to propel the boat at 31 kts with only 10 gallons per hour.
Then there is the issue of whether you want a Diesel that turn 4500 rpms at WOT and has virtually no service and support network in the US.

[Hey Doc]

Stery Repower

I would think those numbers on speed might be close, but again it all depends on the load when you take the numbers. I had a 315 yanmar boat with jackshafts and full atkinson tower. No Generator.

With 5 guys and full load for running to the gulfstream the boat would cruise 31kts at 3300 rpms (18-20 gals per hour). At WOT 3825 it would touch 36.5kts. With not tackle and only 2 guys aboard, it would cruise at 33kts and run 39 kts WOT.

So, the speed numbers are probably somewhere in the right ballpark. I agree with bluefin 32, those fuel burn numbers a probably not correct.

[Patriot]

There is no way a 28 is running 41 Kts with 500 HP.

[Over Billin]

This was my original intent when looking for a Carolina, repower to the Steyr's. Cpt on the Muff Diver had told me about them and did some checking. It all sounds accurate. Only reason I am still running Volvos are for the deal I got on my 02 28 ft CC.

Received a cell call from Cpt Riley while they were sea trialing that 28. At 34 knts he was sitting between the storage cabinets on engine deck, with no background noise at all ! Fuel burn rate at that time was 6.5 gals per hour for both engines. Many additional comments made on the remarkable performence of the Steyrs.

It is my understanding that Carolina boats might be in discussions with the manufacturer.

Over Billin
2002 CC

[Bluefin 32]

Fuel burn rate at that time was 6.5 gals per hour for both engines.

You should go back and check on that 6.5 gph for both engines. Here is the issue. It should take at least 200-220 hp per side to get a 28 going 31 kts even with a jackshaft model, which should be faster than a straight inboard with the same power. A Volvo D6-310 engine, which is a very efficient modern electronic Diesel needs about 11-11.5 gph to produce that much horsepower. Efficiency for reciprocating engines is expressed as something called "BFSC" or "brake specific fuel consumption." The Volvo has a BFSC of around 220. The most efficient Diesels built as test platforms have done better, showing about 200 BFSC (lower is better, it means more power per gram of fuel). According to the data you cited, the Steyr is showing BFSC of only around 125, making it almost twice as efficient as the Volvo.

I am guessing it might have been 6.5 gph per side or about 13 gph total, which would still be impossibly efficient for a motor that was running very near maximum output.

So the fuel burn number cannot be correct and quite possibly the speed is wrong too or least was not the speed at that fuel burn.

I would check this out carefully before spending tens of thousands on a repower. You will never see numbers like the ones you cited. It is a physical impossibility with current technology.

[Split Decision]

I tend to agree with Bluefin32. General rull is 1 GPH per 20HP produced plus or minus. They are getting better all the time but that is a big leap.

[Over Billin]

I can only go by what was relayed to me as they were running and monitoring on fuel flow meter. I have no reason to doupt Mr. Riley. additonally, the President of MSSA has repowered a 31+- Topaz with the same setup months ago. He has stated he typically burns 6 gph total after a few hours on new engines. On first 50 hours he was burning 8 gph total. All runs in the chesapeake bay.

While the 28 was running 34 knts, they still had 600-700 rpms left to tack, but were cautious with such few minutes on enegines.

Additionally, after reveiwing numerous articles on the Steyrs in other equipment, I have every reason to believe that 6-7 gph for 500+ hp is feasable from the Steyrs. Local US rep is here on the Chesapeake. Can provide contact info if needed.

If good results are found with the Steyrs, I'll be repowering with them when the need arises or fuel gets to $5.00 gal. I only have 740 hrs on my KAMD43's and am very happy with Volvo. To repower my setup would run approx 40K, with no trade in value for engines.

[JuliaGCC25]

Assuming your performance numbers are correct, have you done a break-even analysis on the repower?

If you were to lay out 40k today to repower, how long would it take you to recoup that cost? If you put the 40k in a CD @ a measely 4% you would get $1,400 in interest per year before taxes. Assuming you pay 30% tax, that would leave you with about $980 in your pocket to cover increased fuel costs. If diesel goes up $2 that would cover the increase on about 490 gallons. Remember - you would STILL have your $40,000!

If you had to borrow the $ for the repower it would cover an even greater amount of fuel.

In my opinion, the payback period for this investment - considering you have a great set of basically new, low hour engines, would be far too long to justify the expense.

All of this thinking may just as well go out the window because for most of us (me included) a boat is treated like a family member that we spare no expense on!

[Over Billin]

I agree.

My initial intent was to find an existing boat with gas power or blown engines at a reduced rate, then repower. I had found a great deal 5 minutes to late with just that.

I had also looked at the Classea Lady, and Steeple Jack. Given the great deal on Steeple Jack, she is now mine "Over Billin".

To repower It would be at a no choice option, due to unexpected engine failure with my Volvo's. With only 750+ hours on them, I do not expect to due that anytime soon. Prior Volvo's have lasted me > 1500 hrs with no problems. After doing some plant work at Volvo's Hagerstown plant, I can see the quality and pride in their product.

[Bluefin 32]

Don't mean to be grinding this into the ground, but for what it's worth a did a quick search and found this excerpt from a post on boatdiesel from a guy with a Steyr who says the following about his performance and fuel burn (and this is the slightly lower horsepower model).

"My boat is powered by a single Steyr 246 connected via a jack shaft to a MerCruiser Bravo III. I use my boat for fishing, diving cruising-etc. Took delivery early 04. I have about 250 hrs. of operation thus far. My boat is a 27 ft, center console. Top speed is about 40 mph and cruise 30-34 mph. I burn between 6.8 and 9.3 gph @ cruise depending...."

So a single is burning 7-10ish -- meaning the efficiency per horsepwoer is very similar to any other modern common rail electronic Diesel. No magic, but in fairness the Steyr performance would benefit due to much lighter weight-- but not enough to push a 28 Carolina Classic 30 knots at 6.5 gph.

[Over Billin]

Severn River Marine Services in Maryland recently repowered a 28 Jackshaft boat with a pair of Steyrs. Performance was reported at 31 kts at cruise 41 kts at WOT. Fuel burn of 5 gallons per hour each at cruise. Over 3 miles per gallon!!!

Does anyone know this boat/owner?

Diesel

Can find out, know of, through Muff Diver. I beleive his intents were to leave for south Bahamas this Fall / winter. Based on fuel burn rate he is calculating he can make the initial run of 750 nms on main tank.

I am anxious to see if he makes that kind of range ??

[xl883lo]

...........According to the data you cited, the Steyr is showing BFSC of only around 125, making it almost twice as efficient as the Volvo. I am guessing it might have been 6.5 gph per side or about 13 gph total, which would still be impossibly efficient for a motor that was running very near maximum output.So the fuel burn number cannot be correct and quite possibly the speed is wrong too or least was not the speed at that fuel burn.......

Steyr website says min. BSFC for their two 250hp 6cyl marine engines are 215 and 230 which is pretty much the same as Volvo and Yanmar. Go look at the BY260 Yanmar it's even lighter and puts out more torque.

The things that would concern me about the Steyr in a CC28 are the durability of a light weight diesel, lower tourque and operating RPM(both trolling and low speed in slop). Looking at the performance curves it would seem that you are going to have to underprop this engine a whole bunch(much more than a Yanmar) and with the lack of low end torque it should be a real dog both out of the hole and in the slop.

I think if this setup was the ticket you would have seen Mac putting Yanmar BY260's in the 28s already. JMHO

[Patriot]

" I beleive his intents were to leave for south Bahamas this Fall / winter. Based on fuel burn rate he is calculating he can make the initial run of 750 nms on main tank."

Just as I said not CC28 is making 41Kts with 500HP I will add that no CC28 is going to get 750 nautical miles out of a main tank. This is getting stupid, you should advise the USCG now that a fool is about to emabark on an ill conceived journey.