Big Decision Time

[Bob Bradley]

OK, this is going to take a while. I've been running Ambrosia Mae, a '79 43C, since I bought her in 2003. She has 6v92TA engines making 435hp.

When I bought her they had about 850 hrs on them; now around 4000. I seem to be spending more and more time in the ER lately. The port engine has been pretty much bullet proof - the stbd not so much. It eats injectors like Fritos, it seems. Usually 1 or 2 per season over the past 5 or years. Both engines leak like, well like Detroit Diesels. Performance has declined over the past few years as well. Right now I can't seem to get her over 2150rpm. It should hit 2350. I went through the full tune up process on both engines over the past 2 days. A total of 1 injector needed to have the rack adjusted slightly. 3 exhaust valves needed the clearance tweaked. Injector timing was fine across the board. All 4 turbos seem to be spooling properly. Fuel filters are fresh and the Airseps are clean. The stbd aftercooler was last cleaned in '18, the port in '14. It's probably due. Both engines light off virtually instantly this time of year with zero smoke. In cold weather it takes 2 or 3 attempts before they start, and they smoke for 15 – 20 seconds.

I cruise a little with her - mostly fish. I love the offshore scene. Fully loaded heading offshore, I carry 490 gal of diesel in the tanks, 300 more in a bladder on the bow, 165 gal of water, and around 2500# of ice, plus 6 big guys and enough food and drink for an army. I'm lucky to make 15kts heading out heavy, and 16 to 17 heading in after burning off a bunch of fuel. Fully loaded, she probably weighs in north of 48,000 #. On my last trip, we burned approx 710 out of 790 gallons at a rate of 44gph.

So, needless to say I'm getting tired of these engines and I’m tired of the performance. I looked at a '93 50' last week but was disappointed in it. Small cockpit and terrible ER access. I did a lot of soul searching over the weekend while at the boat and decided that I still love her. I've set her up to fit my needs, both for fishing and wifely stuff. New galley, head redone, custom teak cabinets, fairly new electronics, tons of rod holders, etc.

So, I figure my options are:
1) Do the aftercooler cleaning and hope my missing rpm return; live with the oil bleeding and keep cleaning up the mess
2) Rebuild both engines and hope I can live with the performance
3) Sell her and buy another boat with someone else's problems
4) Sell her and buy another boat and repower that one
5) Repower my boat

I'm leaning toward repowering my boat. Yea, I know that the value of the repowered 43C will probably be less than the cost of the repower. I can accept that. I'm gonna be 65 in a few months. Maybe I'm finally having my midlife crisis. I'm not sure I want to keep dealing with the engine problems and marginal performance any more.

So, if you were repowering a 43, what engine would you be looking at? I think I want to be around 635hp and my short list right now includes the QSM11 and the Scania. I know of a '79 43C for sale in North Carolina with the QSMs. They claim it cruises 26kts at 45gph and maxes out at 30kts. I’d be happy with that, presuming its true. I do worry that I might be pushing the envelope relative to having to worry about keel walking at that speed.

So, clearly it’s a big decision for me. I’d love to hear some of your learned opinions on the overall project and engine choice. Thanks.

 

[Boatsb]

Qsm11 is a great motor at 600 or so he. Also the smaller and lighter QSC goes up to 600 bp.

 

[Boatsb]

Qsm11 is a great motor at 600 or so he. Also the smaller and lighter QSC goes up to 600 bp.

Your engines are about 9 liters. Right in the middle of the 2 options

 

[carolinacoast]

We have a neighbor with an 86 43 with Cats. Faster, quiter, and now the second generation family members are using the boat too. Short version, they use it all of the time.
Since you like to fish, Repower and enjoy it as long as you can. It will probably make you smile.

The passion of ownership shines through your post. Have fun.

 

[jim rosenthal]

I'd install QSMs at 660 hp. (they do come with higher ratings, but you can probably get 660hp on the reman program which is definitely the way to go on an older boat) I'd suggest T&S Marine Engines in Crisfield, MD, as the place to buy them. You might be able to get the install done in that area, too.

With those engines, your boat will be substantially faster, burn less fuel, and outlast you. Which a Hatteras will do anyway; they will outlast all of us.

The downside is that you will miss at least part of a season, but if you hauled the boat in the fall, you might get in the water for sea trials by spring.

 

[rustybucket]

Are you installing new/reliabuilt injectors or having yours rebuilt somewhere?

 

[oscarvan]

I've seen the videos of a re-powered 53.... Fortunately, in more than one way, my 8V71TI's were rebuilt 900 hours ago so I would be a fool to yank them out. But if they ever get tired.......

 

[Pascal]

As Jim said the cummins reman program offer excellent value compared to new engines. A good cummins dealer should be able to run the numbers for you, set target speed and do the prop / shaft calculations.

I repowered my 53 MY two years ago with C series mechanical and I m glad I did. I can now cruise at 17 kts and top at 20, which is exactly what the prop shop had estimated. I wish I could have gone for the more powerful QSC but that wasn’t in the budget especially since it would have meant larger shafts.

Yes like everything once you put the new engines on your boat, they instantly loose 50% of their value but since you use the boat a lot, it is probably worth it for you unless you find a boat you like already repowered

 

[racclarkson@gmail.com]

In other words, the best bad investment you’re likely to ever make.

 

[Bob Bradley]

Are you installing new/reliabuilt injectors or having yours rebuilt somewhere?

No. Custom properly rebuilt injectors with matched high and low flow rates from Metro Injection in Deep River, CT.

 

[Bob Bradley]

I'd install QSMs at 660 hp. (they do come with higher ratings, but you can probably get 660hp on the reman program which is definitely the way to go on an older boat) I'd suggest T&S Marine Engines in Crisfield, MD, as the place to buy them. You might be able to get the install done in that area, too.

With those engines, your boat will be substantially faster, burn less fuel, and outlast you. Which a Hatteras will do anyway; they will outlast all of us.

The downside is that you will miss at least part of a season, but if you hauled the boat in the fall, you might get in the water for sea trials by spring.

The reman approach is a good idea. My biggest worry is overpowering her too much. I've heard horror stories about the keel walking problem and I don't want to have to deal with experimenting with cutting the keel.

 

[Bob Bradley]

We have a neighbor with an 86 43 with Cats. Faster, quiter, and now the second generation family members are using the boat too. Short version, they use it all of the time.
Since you like to fish, Repower and enjoy it as long as you can. It will probably make you smile.

The passion of ownership shines through your post. Have fun.

Do you know which Cats? Model and HP?

 

[Avenger]

The reman approach is a good idea. My biggest worry is overpowering her too much. I've heard horror stories about the keel walking problem and I don't want to have to deal with experimenting with cutting the keel.

Watch the talk from the Hatteras engineer. Don't worry about keel walking.:

https://m.youtube.com/watch?v=dirBIsgblt4 Right around the 20 minute mark.

From https://www.samsmarine.com/forums/showthread.php?33668-%93Keel-walking%94-on-series-1-convertibles

 

[rsmith]

Don’t do it. I know your type fishing mission better than anybody. Overnight offshore you really need a 50’+ boat with ample fuel to stay and fish. The best thing we did was buy the 50. 1000 gallons of fuel 2 generators plus the extra space and comfort when things got snotty we could stay in weather everyone else ran from. August 23 1980 we put 9 swords on the boat. We were the only boat at the poor mans canyon because everyone else ran for home.
Plus how valuable is your time at this point of your life? Repowers take not just money but time and aggravation. I don’t care what anyone says nothing goes smoothly there are always problems. One of our former members here repowered his 52 with qsm11’s and had bad vibration issued that the installer could never solve. Last I talked to him he lost 2 seasons and was thoroughly disgusted. Buy something bigger that’s already running with all the bugs worked out. And get rid of the bladder!

 

[Avenger]

BTW, the physics says that 660 HP vs a 48,000 lb boat will top out at about 25 kts with everything else being optimal. How much does she weigh with a normal loadout?

 

[Cricket]

So, being one of the few that has gone down the repower path I understand both sides of the decision.
I do agree with Scott that the 43 really is a little small to be doing your type of canyon trips. Think you would find them much more enjoyable not having to deal with taking extra fuel in a bladder and also the better sea keeping of a larger boat.

But, when you have your boat the way you want and need it to be and the only thing wrong are the engines I say go for it.
Our 8v92's almost ran us out of boating because they just had become unreliable, now it's 20 years after installing the CATS and they still run like the day they were installed.

Might want to look into the CAT C8.7 which is in the mid 600hp range. Remember I'm a believer in having as much HP as will fit and you can afford and then running them at lower RPM's for longevity.
As far as "keel walking" goes that's just a myth, it's a suction issue that can easily be corrected for very little $$$, as posted earlier.
Our boat does get a little wonky when it's light on fuel and in the 27-28k area, we recently tried running it with a rope tied from spring line cleat to spring line cleat and the result was amazing.
Now we just need to figure out were to add the batons on the bottom over the winter.
Only has taken us 20 years to get to figure this out..........

 

[bluedart73]

My two cents ( disclaimer: I don't own this big a boat) but if the repower will need new gear boxes and controls, I would go for much larger engines. Look at the 45-50 Vikings and see what they are putting in these size boats.

Not that you are going to go the 40KNTs of a new boat but the extra power (with the 48k weight) is great in heavy seas and going out with a full load. The boat will "loaf" along rather than "lumber".

48k is pretty heavy.

If you repower (underpowered) you will be a very unhappy camper after a very significant
investment. I think that is why a lot of recent repowers are on the market.

You may also need to look at how large a prop you can clear with the current struts and shafts.

 

[Dan Mapes]

New motor dialog aside, those 6v92's sound ok but the desire for a new engine and some performance is beating a path to your wallet. Are you really going to be able to forego the bladder on the bow?

Sixty five is a good point in life. All things considered would it be that way in 5 to 10 years? As said before 1 or 2 may go into the bin because of the work on the boat to upgrade. If it's all working now I have to ask why bother?

Are those two years worth it? "This ain't no rehearsal".

Here is an example of what you are looking at ->

https://www.yachtworld.com/boats/1979/hatteras-43-convertible-3196186/

If you are close by perhaps a trip to take a look might be a good idea.

 

[jim rosenthal]

I would rough guess that you'll spend 125K, perhaps more, to repower your 43 with QSM11s. They DO burn less fuel- it's possible you might not need the fuel bladder.

At the end of that process you'll have brand new engines (even the remans are new) plenty of performance, better economy, and years of fishing ahead of you. But you'll have to keep the boat to get the value out- not all of it, I suppose, but enough to make you happy.

If the rest of your boat is sound, I'd just repower her.

Incidentally, one of our forum members, Captain Coop, had his 45 Series 2, a similar hull, repowered with M11s and she hit over 34kts on trials. Not fully loaded- could have taken a bit more pitch in the wheels. So yours should feel quite sporty when you're done.

CAT makes some decent engines, but in this segment of the market, I think the M11s are the preferred powerplants. Which means if you ever DO decide to sell and buy a bigger boat, you'll get a little more for the current one.

Also, 6v92 cores are not valueless- sell them in B&H and get yourself a few bucks back.

 

[SKYCHENEY]

The QSM11 has dry manifolds and turbos. This has caused some issues in some boats with warped manifolds and sooting. If propped right to keep the heat down at certain RPM, they are said to be okay. But, I would prefer an engine with water cooled manifolds and turbos. The heat in the ER would be less and less chance of fire.

The Cat C12 was produced in a compact model that might work. Don't just look at HP, its the torque that matters. Don't go with fast turning engines that run 3000 RPM. The torque will not be sufficient.

Which model Scania are you considering? Cat and Cummins would obviously provide the most service locations but that may not matter if you fish out of the same area all of the time anyway.