Detroit with sterndrive?

I'm in the progress to convert from gasoline v8 volvo penta to a diesel.
I'm looking into a 6V53T or something like that, but I need a stern drive.
Could anyone suggest me a stern drive for south a engine?

 

A #8 Arneson.

 

Yes, a VolvoPenta with the proper gearing. What happened to your sterndrive?

 

6V53TI is 2,325 lbs/1,055 kgs and 400hp at 2800 rpms. It is a completely different animal than a gas V8. I have never seen one used in a stern drive application but would think it would need something along the lines of a heavy duty commercial type drive leg to handle the torque and large propeller size to make it perform properly that is if it doesn't sink the boat stern first before you can get under way.

 

This is absolutely true. I love DDs but everyone I have seen is attached to some kind of shaft via reduction gear tranny of considerable size.

 

1 metric ton!!! From the data I have found they weight 600kg witch is also alot, but I could live with it. 1 ton on the other hand.
I was looking at bravo drives and they deliver diesel drives up to 320hp, but I'm not sure what propeller RPM I should have.
I can't find data for pitch and stuff like that so it's not so easy.

 

Volvo makes a lot of small high speed (3700 to 3900 rpms/500 kilos) diesels for stern drive applications. Can you find any of those around used? Maybe a running take out of a twin set that was removed for a repower.

 

The low RPM torque of that DD engine would probably destroy most any 'consumer class' (mercruiser, volvo, OMC) sterndrive in a short period of time.

There are a few heavy duty drives that are marketed that might stand up such as the B-Max. I imagine they come with a pretty hefty price tag to match.

 

I lost all faith in volvo after my father used them for more than 10years in a ambulance boat. We had two total engine failures and a 3d after we sold it.
We had a blown head gasket right after the warranty expired that according to a local volvo engineer was a production error, but got nothing back.

 

A 3000RPM engine with 500Nm and a 3:1 gearing will put the same load on the parts after the reduction as a 1500RPM with 1000Nm and a 1,5:1 gearing.

 

Cummins 4BTA3.9 up to 240 hp might be something you could use but I have no clue where to get one. I have a feeling you might have the same results with Yanmar as you did Volvo. Neither is a heavy duty diesel in the power range you are looking.

 

I like the cummins. I used to work on them when I was a motorman on a offshore vessel 12years ago.
I feel that there is lots of engines that are better than the detroit since I would need a full sett of none metric tools(witch suck) , but I feel the two stroke have a bad reputation witch it don't deserve and I think I could get some more out of it by applying som modern turbos and electronic control.
Found out they are about 600-700kg and not a ton, but wonder what the military aluminum version weight if it's possible to get it for a fair price.

 

The figure I gave you was for a fully marinized version including manifolds and bell housing from a DD spec sheet. The I4 or even I6 cummins would be less work to marinize than a V-motor since it only has one exhaust manifold. Much lighter and 240 to 330 hp would likely get the job done. If you like noise though go for the 6V53. Only thing louder is and 8V53

 

Cummins Mercruiser will give you a 1 year or 400 hour warranty on their QSB 5.9/Bravo 2 package with an intermittent duty cycle commercial service which stipulates cruising RPM is 200 RPM below rated output of 169kw at 3000 RPM. The the engine outputs 168Kw and 574Nm of torque and at cruising RPM of 2800. Commercial warranty is not available with any other package. Bravo II available drive ratios are 1.81:1 - 2.20:1.

This does not give much confidence in the drives ability to withstand diesel engine output.

Extrapolating this with the DD 400HP @ 2800 RPM, you can probably expect the drive to last about 200 hours more or less.

 

A DD does not have more torque than a Volvo Penta of similar horsepower. Look at the specifications before posting.