Marine diesel

[3rdday]

Is there a special outdrive for diesel engines? Beefier gears and different ratios since diesels turn lower rpms in thier optimum ranges?
Would an outdrive that was originally mated to a 350 work effectively ( I know diesels turn less rpm than gas and have more torque) with a diesel. Will the outdrive handle the torque?
If not, Can anyone reccomend a diesel and outdrive setup for a 2800 lb 22ft. craft? Prefer turbo diesel. I hear VW has a new sweet marine 6cyl turbo diesel.

[Fr. Frank]

95 through 465hp Cummins engine/Mercruiser drive matched sets, or
110hp through 375hp Volvo diesel/Volvo Penta drive, or
105 through 450 Yanmar diesel/Mercruiser drive sets, or
185 & 220 hp BMW diesel/BMW MkII drive.

The Cummins/Merc setup will give you access to the most service points, and the Bravo drives are very reliable.

I also found mention of 220 & 310 hp Mercedes diesel engine/OMC drive combos being sold in Australia.

The only mention I could find of a Volkswagen diesel/stern drive combo suggested that the VW would be mated to a Volvo drive in the future and available in a 80 and 120hp config.

Can anyone else find more info?

[3rdday]

I did some research an d found the VW is avail in 165 HP and 225 HP mated to the bravo . The numbers on the example boats(specifically 20-22 ft boats) were impressive in terms of speed and fuel consumption. look at the WOT and Cruise Ranges and fuel consumptions , look at the speeds WOW !
http://www.vw-m.de/index.php?id=172&L=1&tx_prisreferenzboote_pi1[view]=details&tx_prisreferenzboote_pi1[uid]=35&tx_prisreferenzboote_pi1[amotor]=9&tx_prisreferenzboote_pi1[dstart]=10
I also discovered Ring Power is distributing and servicing them.

[JohnB]

Top Speed: 45 knot
Cruising Speed: 40 knot

Consumption by Full load WOT: 13 gallons (US) / hour 0.29 gallons (US) / nautical miles

Consumption by Cruise: 7.9 gallons (US)
0.2 gallons (US) / nautical miles

They don't know how to do math on that engine.
WOT of 45 knots burning 13 gph is about 3.9 miles/gallon, not .29 and cruise is 5.8 miles/gallon. The range is off a tad, but at least it's close.

[3rdday]

In your opinion is that good economy in respect to gas I/O and Outboards ? Seems double or even triple compared to an outboard of same or close HP. remember this is thier 225 HP take a look at some of the 165 HP boat references.

[JohnB]

First, that is not an apples to apples boat. Ski boats are usually flat in the back, have alot less wet hull area, and run on flat lakes, not the open ocean, compared to a 23' seacraft. IMHO, you could probably get close to the milage in a 4 stroke outboard, all boats being equal. I think that type of inboard would give you a little better milage (10-15%), and the outboard would give you better performance, it's a tradeoff, that's just my opinion.

[76Red18]

VolksVagon just dosn't sound "badass" enough to be married to a beauty like a SeaCraft . I'm sure its a good product though just my 2 pennies

[JohnB]

VolksVagon just dosn't sound "badass" enough to be married to a beauty like a SeaCraft . I'm sure its a good product though just my 2 pennies

If gas wasn't 3 bucks a gallon, I have a 426 hemi that would probably move a seacraft along just fine, and sound even better.

[76Red18]

If gas wasn't 3 bucks a gallon, I have a 426 hemi that would probably move a seacraft along just fine, and sound even better.

Lake Pipes and all!

[GradySailfish]

What kind of diesel do you want to put into what kind of boat. The lower end-powered diesels won't harm a Alpha sterndrive, but the upper end stuff is creates too much torque for a alpha and require a Bravo class drive.

Volvo makes the best drives although I'm not sure what series of drives can handle certain diesel power, but I'm inclined to say I prefer a volvo drive to a merc drive.

That said, my Grady White Sailfish has twin Cummins Mercruiser 1.7 DTI 120 HP a piece diesels mated to Alpha X drives. So far so good, but those drives are actually reinforced Alpha drives (they are called Alpha X drives)

Basically it is feasiable with great reliability, but you need to make sure the drive can handle the power.