Navstar 7.3 diesel Marinizations?

doughnut · 03-09-2010, 03:01 PM

I have seen some boats powered with the Mercruiser 7.3 Diesel. This looks to be a marinized Navstar 7.3 power stroke. Sounds good, but not much info out there. Any experiences?

stringer bell · 03-09-2010, 03:52 PM

I have seen few, they make about 180-200hp, used mostly in commercial boats. not sure about longevity, but based on road version 7.3 they should be bulletproof

doughnut · 03-09-2010, 04:12 PM

Quote:

Originally Posted by stringer bell

I have seen few, they make about 180-200hp, used mostly in commercial boats. not sure about longevity, but based on road version 7.3 they should be bulletproof

Thanks

The Mercruiser/Cummins rates them at 260 or 300 HP

dougl33 · 03-09-2010, 04:40 PM

If you're going to spend money for a diesel, buy a name brand (Cummins, Yanmar, Volvo, Nanni, etc...). If you can't swing that kind of money then stick with gas. Parts will hard to get, you'll have a hard time getting service, re-sale will suffer. This is one trail you do not want to blaze.

Head over to boatdiesel.com and spend the $25 to browse the archives.

Moby1 · 03-09-2010, 05:19 PM

Try searching for Starpower diesels. I believe they marinized a few of these. Good luck!

doughnut · 03-10-2010, 07:41 AM

Quote:

Originally Posted by dougl33

If you're going to spend money for a diesel, buy a name brand (Cummins, Yanmar, Volvo, Nanni, etc...). If you can't swing that kind of money then stick with gas. Parts will hard to get, you'll have a hard time getting service, re-sale will suffer. This is one trail you do not want to blaze.

Head over to boatdiesel.com and spend the $25 to browse the archives.

I would agree, but, in this case, the boats already have this power plant in them. I would think ( with 0 experience with the motor other than in trucks) it should be pretty good. I was just looking for some real world experience. Not much at boatdiesel on them.

EODContender · 03-10-2010, 08:09 AM

Quote:

Originally Posted by dougl33

If you're going to spend money for a diesel, buy a name brand (Cummins, Yanmar, Volvo, Nanni, etc...). If you can't swing that kind of money then stick with gas. Parts will hard to get, you'll have a hard time getting service, re-sale will suffer. This is one trail you do not want to blaze.

Head over to boatdiesel.com and spend the $25 to browse the archives.

I didnt know Navistar / International wasn't a name brand.......since when did they start knocking off diesel engines???????

bjm9818 · 03-10-2010, 08:36 AM

I didn't know Navistar / International wasn't a name brand.......since when did they start knocking off diesel engines???????

Never heard of them before...LOL ... that 1993 F250 Diesel I had with 289,000 miles and still running I sold a year ago had a terrible engine.

jerseysportfisher · 03-10-2010, 08:53 AM

Quote:

Originally Posted by bjm9818

I didn't know Navistar / International wasn't a name brand.......since when did they start knocking off diesel engines???????

Never heard of them before...LOL ... that 1993 F250 Diesel I had with 289,000 miles and still running I sold a year ago had a terrible engine.

WOW

You never heard of International Harvester , International Truck ? they have been around since early 1900's ?

bjm9818 · 03-10-2010, 08:56 AM

was quoting EODContender's sarcastic post above mine.... Was a joke, I had the 7.3 International in my F250 great engine...

SteveA · 03-10-2010, 09:28 AM

My 10 year old Power Stroke hasn't missed a beat in a decade. I was hoping that we would someday see them in boats.

SIM · 03-10-2010, 10:36 AM

I don't have any experience with the 7.3's in a marine application, but using them in a truck and using them in a boat are two different things. Example.......go and put a full load on your pickup truck and hold the pedal to the floor mat...................for an hour.

Not saying that they couldn't do it, just trying to say that a p/u truck and boat application are two different things.

I have a 2001 7.3psd with 235K on it and I love that engine.

marlinmike · 03-10-2010, 10:48 AM

I always wondered why this engine never took off, even with Mercruiser backing it, but it failed in the sales department and therefore dropped (not uncommon for Mercruiser). One problem with this small install base and limited marine production run, limited parts (for now) and less then stellar resale value.

If you can get it for a steal then go for it, at least it is setup with diesel and repowering to Cummins or Yanmar in the future is not that difficult.

EODContender · 03-10-2010, 11:09 AM

I think Yanmar actually had a 7.3 at one time based off of that engine, but I may be wrong. Dont quote me on that.

SIM · 03-10-2010, 12:16 PM

Quote:

Originally Posted by EODContender

I think Yanmar actually had a 7.3 at one time based off of that engine, but I may be wrong. Dont quote me on that.

To late!!

dougl33 · 03-10-2010, 06:35 PM

Quote:

Originally Posted by EODContender

I didnt know Navistar / International wasn't a name brand.......since when did they start knocking off diesel engines???????

Then go ahead and buy a boat with them and let me know how it works out.

Oh yeah, then go ahead and try selling said boat.

Trucks and marine apps are apples and dump trucks.

dougl33 · 03-10-2010, 06:40 PM

Quote:

Originally Posted by doughnut

Not much at boatdiesel on them.

I think that pretty much tells you everything you need to know.

EODContender · 03-10-2010, 07:41 PM

Quote:

Originally Posted by SIM

I don't have any experience with the 7.3's in a marine application, but using them in a truck and using them in a boat are two different things. Example.......go and put a full load on your pickup truck and hold the pedal to the floor mat...................for an hour.

Not saying that they couldn't do it, just trying to say that a p/u truck and boat application are two different things.

I have a 2001 7.3psd with 235K on it and I love that engine.

I have actually done it....all the way to Louisiana after Katrina. Left South Florida hauling a 32 cu/yd goose neck dump trailer with a Bobcat in it (18,000 lbs), with a 80hp chip in it. Had to get there as fast as possible for a pending contract. Ran over night and never got below 80mph. Had a 100 gal aux fuel tank as well, so fuel stops were pretty far appart.

The internal workings of the motor are the same, with the possible variation in the cam. The differences will be the exterior finish, and cooling system. I wouldnt be too concerned with it.

I do agree, by the way, that a truck and boat are completly different applications. I just know that motor has proven itself.

obbayer · 03-10-2010, 08:04 PM

An important part of this would be the transmission and the prop and where in the RPM/Torque curve sweet spot the engine ends up running.

doughnut · 03-11-2010, 08:14 AM

Quote:

Originally Posted by dougl33

Then go ahead and buy a boat with them and let me know how it works out.

Oh yeah, then go ahead and try selling said boat.

Trucks and marine apps are apples and dump trucks.

If this is true, then the 6BTA Cummins (any Cummins), 3208 CAT(any CAT) Yammar (Toyota truck 6cyl) etc should not be succesfull in marine applications.

I agree that the odd motors are hard to sell. For example, a boat with a Fiat six diesel is hard to sell, yet with a Cummins, its not. Funny really, in that they are the same motor.