1050 MANS in a 46C

[captddis]

It runs great. I have a '74 46C and she runs better at 23-24kts than she does at 18-19kts. Boat gets up a bit higher and really knocks down the chop. Spray seems a bit less at the higher speeds. The 46C HP boats w/8V92's are the same hull with the keel shortened. If you are referring to the early 90's 46C, that is a completely different boat.

The hull form is the same but it was beefed up on the HP models with extra tranverse stringers, the engine bed was reinforced and has 2 1/2 shafts and the double bearing struts and big rudders. centerline fuel tanks and a revamped electrical system and A/C systems as well as a redesigned interior.
The hull is balsa cored on the sides for stiffness and weight savings too.

Agreed on the speed and I was involved with a 1975 46C that was repowered with 565 HP 6V92 DDEC. The boat was stable at 26 kts.

I don't see a problem repowering these boats as long as common sense is used the throttles pulled back when it gets rough.

[saltshaker]

The hull form is the same but it was beefed up on the HP models with extra tranverse stringers, the engine bed was reinforced and has 2 1/2 shafts and the double bearing struts and big rudders. centerline fuel tanks and a revamped electrical system and A/C systems as well as a redesigned interior.
The hull is balsa cored on the sides for stiffness and weight savings too.

Agreed on the speed and I was involved with a 1975 46C that was repowered with 565 HP 6V92 DDEC. The boat was stable at 26 kts.

I don't see a problem repowering these boats as long as common sense is used the throttles pulled back when it gets rough.

The first thing I noticed when looking at the pic of your boat was the larger main strut and the different rudders. Seems a bit of overkill but what you would expect from Hatteras. The running gear on my 46C is bigger than that of most bigger boats with larger engines. These old Hatts are overbuilt which makes them great candidates for repower. I wouldn't be as concerned with structural issues as I would be of design issues. Most models can handle an increase in speed. It takes a huge amount of HP to push these boats to a cruise in 30-35kt range. As you stated you need to use your head when seas pick up. Even newer boats that were designed to run fast need to slow it down when conditions are less than perfect.

[Captned]

I saw a an older Hatteras sportfish that was repowered with big Yanmars. The guys fished it alot. Would do over 30 knots. After a couple of months of use, it started coming apart. Lots of tabbing failures, etc.. They sold the boat.

Captned
MBMM

[captddis]

I remeber asking one of the captains what the boat started out as, I do recall he did not say it had been a 46. I think he said a 45C, I know it was cut down to an express. Have you ever head anything on how it performed, and is it still for sale? Who did the engineering on the hull?

It was a 46C HP. Slane did the renovation and initially put 6V92s in it, the boat was not fast enough and the RR engines were installed at Great American by Slane. I want to say around 1994 or so. It was named Makaira and owned by a Home Depot exec. Because it was a factory HP model it was already built by Hatteras to handle the power. It should be obvious whether it was a 45 or 46 they are different hulls


Go to the Slane website and click on projects and you will see the boat.

[saltshaker]

The express boat was, as Dave said a 46C HP that had burned. I've been on the boat a few times and she is impressive. Stood in the ER with Tom, and two others and we had plenty of room. Owners brought the boat up from NC and claimed she ran 28-30kts with calm or choppy seas. I know they had some issues getting parts for the engines and eventually repowered with new surplus 8V92's. They were looking into 800-1000hp Manns but decided not go that route due to cost. That owner has since sold the boat but I see him from time to time. He says it is one of the best and most predictable boats he has ever run.

The other boat with the Rolls engines is a late 60's/early 70's 45C. Slane also did that boat. Don't know much about it except that Tom claimed the owners put several thousand hours on her with good results. I think he said she cruised in the 29-30kt range.

[saltshaker]

I saw a an older Hatteras sportfish that was repowered with big Yanmars. The guys fished it alot. Would do over 30 knots. After a couple of months of use, it started coming apart. Lots of tabbing failures, etc.. They sold the boat.

Captned
MBMM

If that is the same boat I'm thinking about, she had been in charter service most of her life, went through several majors to the 8V71's and had tabbing issues before she was repowered with the Yanmars. I think it had a full length spray rail that was done incorrectly making for a stiff ride. I was told that all the pounding was what caused the tabbing issues. The rail was modified the boat was repaired and sold.

[saltshaker]

I don't think we are talking about the same boat. I have been on the boat, and stayed at the marina it was berthed at. Maybe there are 2 with RR engines in it.

Which one the express or the SF? Not too sure there were any more out there. The 46 express that Dave and I mentioned is the same boat. There are a few other Hatteras Express conversions out there but I doubt they would have the Rolls engines in them. The convertible may be but again I think Slane was the only one who used those engines and I know he did the express and a 45C.

[Spellbound]

Captddis is correct regarding the 46' express formerly named Makaira. I fished the Bertram/Hatteras shootout with Tom Slane and Bruce way back when. Boat did in excess of 32kts WOT (keel walked) and cruised an easy 29-30kts in most sea conditions. We actually won a Treasure Cay tournament that same year we fished the shootout. Engines were very tempermental reagarding fuel filtration -- the screens/filters would clog often with very little warning. Parts were difficult to obtain as stated above due to these engines were basically one-offs.

Boat was tough as nails and we fished some rough areas over the years. Tom built another 46' almost exactly like Makaira named Rocky Bluff. This boat lived in Bradenton/Palmetto at owners development and his house in Boca Grande. He now has a 58' Donzi express that is kept at Los Suenos Costa Rica year round. Both boats were fast, seaworthy and good fish platforms.

[saltshaker]

This is the 46 express formerly Makaira. The listing says she was repowered in '94 but that is incorrect. I was on the boat with Tom in the fall of 2002 and she still had the Rolls engines in her.
http://www.yachtworld.com/core/listi..._id=54449&url=
and here's the original
http://slanemarine.com/makaira.html

[George]

Running strakes and spray rails will lift and stabilize. after that, put an Ocean Yacht logo on the side, as she will remind you each and every day that you put on additional spray rails. she will pound you like veal.
good luck. everyone else here has suggested all your options.