1988 48 hatteras convertible repower

[hoodie55]

Hello I have a 1988 48 hatt convertible I am looking at repowering the engines I have been thinking about using are the volvo d13 800 hp scania di13 in 800hp and the nanni n13 cr3 800hp would like everyone's opinions on these engines or if some one has repowered a 48 in the past there expertise. Thank you

[Boatsb]

What options will fit best. Length can be the issue. Also down angle and height.

Get a good dealer who can make it work. It's not a simple job.

[Bob Bradley]

Hello I have a 1988 48 hatt convertible I am looking at repowering the engines I have been thinking about using are the volvo d13 800 hp scania di13 in 800hp and the nanni n13 cr3 800hp would like everyone's opinions on these engines or if some one has repowered a 48 in the past there expertise. Thank you

I looked at the Scania motors in 2019 when I was considering repowering my '79 43C. I was just sick of dealing with the 435hp DD 6v92ta engines. I can't recall which model I was looking at but they were well under 800hp. Sticker shock got me boat shopping instead. IIRC, back then the total job (engines, gears, shaft replacement, and ER work) had the job north of $250k. My shopping landed me in a 1986 45C with Cummins QSM11s at 535hp. I'm very pleased with the decision to buy one already repowered. I'm now cruising effortlessly in the 21kt range and I top out around 29kts. At 21 my fuel burn is around 35gph combined. Big improvement on the 42gph at 17kts in the old boat. The Scanias did come very highly recommended by my DD guru here in CT. He likely has over 50 years experience on Detroits by the way.

[motoryacht lover]

I would not go with Volvo. I have a friend that is a Volvo dealer and they are very difficult to work with and the parts are very expensive. Last spring I was in a shop that was a Scania dealer as well as Cummins and MAN and I asked what he thought about the scanias and he said parts availability was an issue and this was last spring (well past covid).

[rsmith]

What he said. Repowering never makes sense. Every one is a custom job that as anyone who’s honest will tell you the cost overruns are significant and the success of the installation is dependent on the installers. Better to pay up and find one already done that you can test run. Plus the 48C was never a well received model. They have never brought the money a series 11 45 or 52c has. Like the series 11 50 also. I had a friend had a 48C he passed and I helped the sons sell the boat. It was 2012 but we basically gave it away for $36k 500 hours never fished and sat at the same yacht club in Vero beach all its life. Some of the legacy members here will remember it.

I looked at the Scania motors in 2019 when I was considering repowering my '79 43C. I was just sick of dealing with the 435hp DD 6v92ta engines. I can't recall which model I was looking at but they were well under 800hp. Sticker shock got me boat shopping instead. IIRC, back then the total job (engines, gears, shaft replacement, and ER work) had the job north of $250k. My shopping landed me in a 1986 45C with Cummins QSM11s at 535hp. I'm very pleased with the decision to buy one already repowered. I'm now cruising effortlessly in the 21kt range and I top out around 29kts. At 21 my fuel burn is around 35gph combined. Big improvement on the 42gph at 17kts in the old boat. The Scanias did come very highly recommended by my DD guru here in CT. He likely has over 50 years experience on Detroits by the way.

[Pascal]

I would prefer something with better parts availability and service. I ve heard good things about Scanias but they re not “mainstream” enough unless you have a reputable dealer nearby. Volvos are good but parts and service are a little mor expensive and harder to get

Doesn’t Cummins have something in the 700hp range? Their factory remans are fantastic value. Cat also has a factory reman program now. Worth looking into

Nowadays with chain supply issues domestic engines are a plus, assuming they haven’t outsourced. Last year we waited 4 months for an 16V2000 MTU crankshaft for the boat I run. It turned out it was made in India, shipped to Germany for inspection before arriving here.

[jim rosenthal]

Both Cummins and Cat have reman programs; Cat is new to the reman game, Cummins have been doing it forever.

The 48 convertible Hatteras was not a popular boat for Hatteras Yachts and they didn't sell many of them. If you've had her a long time and you are very happy with her, go ahead, but at the cost of a repower you will need to own and run the boat a very long time. When it's time to sell she will still be a model they didn't sell many of- although she may be the best one in the world. Food for thought.

A huge factor is the repower yard and their familiarity and comfort level with whatever engines you choose. For example, if they've done several jobs with Cat and Cummins engines, and none with FPT or Scania, that would definitely steer my choice. Also think about where you are and which dealers are close to you. You don't want to have your warranty-work dealer hundreds of miles away if you can help it.

Cummins have M11s in that range, but 700hp is at the top of what that engine produces, and there have been comments here (and elsewhere) talking about exhaust manifold failures on M11s. On a boat that size and weight, I would be looking at a 3406E or whatever the modern equivalent of it is- a C18, maybe?

[captcrunch]

I’m In the process of finishing a repower on my 1988 38c which is very similar. Most likely will need a down angle gear. I am putting in a pair of c9 cats that were running takeouts. You have several quality choices of motor options and I would include the fpt options as well. Aside from engine and gears, there is all the ancillary items. A lot of the things in the engine room (hot water heater, waste pump, AC compressors) need to be relocated as a lot of the newer engines are shorter but wider then the original Detroits, and many of these items it may pay to replace at the time depending on age. Then there’s always a lot of old wiring, old transducers that might as well be pulled and glassed at the time, etc.

[hoodie55]

What is everybody's thought on cummins qsm 11s at 715hp in the 48 hatteras I might be able to get my hands on a pair of them with gears for a good price

[SKYCHENEY]

What is everybody's thought on cummins qsm 11s at 715hp in the 48 hatteras I might be able to get my hands on a pair of them with gears for a good price

Go on Boatdiesel and read about them. They wouldn't be my first choice.