Engines for my 42' Hatteras LRC

[SIBERNUT]

And if you needed another nail in the DD coffin, the 53's were wet liners. 71's were dry.

 

[PierreR]

You own the hull at this point, no matter what engine you install it will not change the hull design so the decisions on what engines to put in should be greatly deminished without destroying the boat. you should have made the decision on what “cruise speed” you wanted before buying the boat not choosing engines to replace based off of that. Changing engines will not change a semi displacement hull into a full displacement hull, if you want a full displacement boat go buy one..

I want to go at displacement hull speeds of7.5 knots in open water conditions. Physical disabilities dictates that I should have bought a houseboat with an elevator. I think the LRC is a fair compromise.
I am well versed in hull design and diesel power. What you are saying is mostly true but not entirely accurate. If 95% of my motoring will be at 7.5 knots or lower, I would rather pick and engine size that is running near or just under the sweet spot for those engines.
In any case, I am not repowering yet, I can buy a lot of diesel for the price of repowering even though I would be doing all the work myself.
My wife is dictating more of my boat decisions than logic or resale. Logic would have meant I would never have sold the boat I built for this new boat.

 

[Mako]

"Which also means that the difference between two 50hp engines or two 150 hp engines to pushing a boat at say hull speed will have no appreciable difference in fuel burn."

"If 95% of my motoring will be at 7.5 knots or lower, I would rather pick and engine size that is running near or just under the sweet spot for those engines."​

That first statement is entirely false and just because people say it over and over, doesn't make it truer and truer.

The second statement is entirely correct.

Engines, even the same model but with different ratings, all have unique specific fuel consumption curves. A typical model can very well burn (SFC) 15% or more fuel at low load versus at its sweet spot at higher load. Some are vice versa.

15% is a significant difference for a long range cruiser. Add to that the 15%-25% fuel savings from trading the Detroits for a modern mechanical, and now you've increased your range by 30%. Clarifying, I'm referring to mechanical engines, which appears to the be interest of the OP.

 

[Keysdisease]

The 42 LRC has very good sound deadening,

Respectfully, never been on a Hatt with what I would call "very good" sound deadening. I might characterize the treatments I have seen in the more vintage Hatt's as good enough to sell boats, the newer ones not so much.

The OP has expressed that quiet is a priority, and the intake stroke noise from a natural DD can be teeth rattling. It's also a low frequency noise that is very difficult to control.

Attention to combustion air paths and bulkhead and overhead penetrations along with a proper insulation scheme can improve the typical Hatt noise levels. Attention to engine mounts and exhaust can bring a noise control plan up to "very good."

$0.02

 

[Jmarsh203]

And if you needed another nail in the DD coffin, the 53's were wet liners. 71's were dry.

Wrong both were dry, 92 series were wet. Wet liners tend to be much easier to replace so no nail in the coffin anyway.

 

[garbler]

Wrong both were dry, 92 series were wet. Wet liners tend to be much easier to replace so no nail in the coffin anyway.

I don’t think so. I was just in a shop last week on a 671 rebuild and the kit had liner O-Rings. The 92’s modified their liners and O-Ring placement.

Rick

 

[garbler]

And why is a wet cylinder liner a negative ? You do know that most all heavy duty marine and industrial diesels have wet liners. This feature runs from Detroits, John Deere, Luger, Caterpillar, Gardner, Iveco, EMD, MAN, MAK, Fairbanks Colt, the list continues in several languages. Wet liners provide superior cooling to liner and pistons opposed to dry liners which rely on metal to metal conductive heat transfer. This means with wet liners you can normally do in-frame rebuilding as opposed to block-to-the-shop on dry liners where the block-usually has to be clean up bored for proper liner fit.

Overheated dry liner engines can warp blocks which mean a new engine most of the time. Overheated wet liners can gall or pull metal but a Detroit mechanics can swap them out. It’s true that if the lower O-ring leaks oil it can weep into the crankcase and top o-rings can let coolant into the air box and cause steam in the exhaust and/or blown head gaskets but any operator paying attention should see white exhaust, high temps and greenish looking oil on a dipstick from coolant contamination. But this is certainly not common on standard rated HP non modified engines.

It cost the builder more to make a wet liner engine and the liners are always heavier or thicker. Manufacturing cost is everything these days especially with smaller high speed pleasure boat diesels. Companies like oilfield drilling companies have Detroits running almost all their vessels and they run them very hard. Often they do in frame rebuilds or they just pull new rebuilds from the shop. It’s almost rare to have to replace cranks and often rod and journal bearings aren’t swapped. The Detroits are true modular engines probably the first, so rebuilds have historically always been much easier, cheaper and accomplished in the field or in-frame. If you hot rod these Detroits with performance parts bigger injectors you’ll get more HP but rarely more than about 5K hours. And yes Detroit two cycles weep some oil some worse than others but a lot of this has to do with the way they are run and regimented maintenance.

Rick

 

[hollywood8118]

I have been starting to look at Hatteras 48LRC's, All except two that I have seen in the last number of years have the DD4-53. One had Lehman's, another had John Deere's. There must be a reason they as seem to keep the retched Detroit's. I have no issue with the Detroit's as they are simple, easy to repair pretty much anywhere and seem to last forever. I'm still a skeptic in regards to the electronic controlled diesels. I know they can be run at any rpm and sip fuel, never smoke, start instantly but if remote voyaging is in the plan ( it is for me ) the mechanical motor is preferred. I sat in a remote anchorage in Panama once in the mother of all lightning storms and worried about the computer and paraphernalia on the John Deere. The repower cost on the Op's boat will never be realized when the boat is sold to the next owner. If it was my boat since the motors run fine now I would spend $10k on sound attenuation and run the Jimmy's

HOLLYWOOD

 

[Delta Riverat]

Yeah, me too. Same mounts, same tranny and historic reliability and durability.

 

[Crux]

And why is a wet cylinder liner a negative ? You do know that most all heavy duty marine and industrial diesels have wet liners. This feature runs from Detroits, John Deere, Luger, Caterpillar, Gardner, Iveco, EMD, MAN, MAK, Fairbanks Colt, the list continues in several languages. Wet liners provide superior cooling to liner and pistons opposed to dry liners which rely on metal to metal conductive heat transfer. This means with wet liners you can normally do in-frame rebuilding as opposed to block-to-the-shop on dry liners where the block-usually has to be clean up bored for proper liner fit.

Overheated dry liner engines can warp blocks which mean a new engine most of the time. Overheated wet liners can gall or pull metal but a Detroit mechanics can swap them out. It’s true that if the lower O-ring leaks oil it can weep into the crankcase and top o-rings can let coolant into the air box and cause steam in the exhaust and/or blown head gaskets but any operator paying attention should see white exhaust, high temps and greenish looking oil on a dipstick from coolant contamination. But this is certainly not common on standard rated HP non modified engines.

It cost the builder more to make a wet liner engine and the liners are always heavier or thicker. Manufacturing cost is everything these days especially with smaller high speed pleasure boat diesels. Companies like oilfield drilling companies have Detroits running almost all their vessels and they run them very hard. Often they do in frame rebuilds or they just pull new rebuilds from the shop. It’s almost rare to have to replace cranks and often rod and journal bearings aren’t swapped. The Detroits are true modular engines probably the first, so rebuilds have historically always been much easier, cheaper and accomplished in the field or in-frame. If you hot rod these Detroits with performance parts bigger injectors you’ll get more HP but rarely more than about 5K hours. And yes Detroit two cycles weep some oil some worse than others but a lot of this has to do with the way they are run and regimented maintenance.

Rick

All of the above is true.

And the 71 dry liners take mich more skill to correctly install.

With the old liners out and everything cleaned up, you start 'selectively' fitting liners to 'basic' block bore. You start with 3 test liners...a standard outside diameter, a .001 oversize liner, and a .002 oversize.

You begin by test fitting, by hand, each of the 3 sizes in each basic block bore. Going in freely is too loose and will not transfer heat....going in requiring hard palm force, or more, is too tight and will distort liner causing early piston scuff....perfect, is a snug,mushy,draggy, top to bottom uniform feel.

Once discovered, you assign that particular part number/size liner to that cylinder. When finished with all cylinders, you purchase those specific sizes needed for that particular engine.

If a liner fit is found to be too loose, you can still recover.....a .010 oversize outer diameter liner is available....requires machine boring the basic bore .010 oversize....now that cylinder is back in spec.

So....yes, the wet style is much easier, requiring none of this.....just make sure the block liner O-lands are in good, sound shape. We have two 3-53's here now for overhaul....running in small graders.

 

[twistedtree]

All of the above is true.

And the 71 dry liners take mich more skill to correctly install.

With the old liners out and everything cleaned up, you start 'selectively' fitting liners to 'basic' block bore. You start with 3 test liners...a standard outside diameter, a .001 oversize liner, and a .002 oversize.

You begin by test fitting, by hand, each of the 3 sizes in each basic block bore. Going in freely is too loose and will not transfer heat....going in requiring hard palm force, or more, is too tight and will distort liner causing early piston scuff....perfect, is a snug,mushy,draggy, top to bottom uniform feel.

Once discovered, you assign that particular part number/size liner to that cylinder. When finished with all cylinders, you purchase those specific sizes needed for that particular engine.

If a liner fit is found to be too loose, you can still recover.....a .010 oversize outer diameter liner is available....requires machine boring the basic bore .010 oversize....now that cylinder is back in spec.

So....yes, the wet style is much easier, requiring none of this.....just make sure the block liner O-lands are in good, sound shape. We have two 3-53's here now for overhaul....running in small graders.

I though these engines were simple and easy to rebuild?

 

[Crux]

Takes only a couple of minutes per cylinder to check and select....

 

[fgarriso]

I think this thread started with a question on DD engines were they too loud and if needed sound attenuation. The answer is yes all of the two stroke DD engines are very loud in compared to most other diesels. I have two of them and wish I could replace them with John Deeres, but do not have the funds at this time. The cost of replacing the engines, transmissions, and controls is 80 to $100,000. With that you may as well do the generators to, and freshen up the engine room.

 

[Muriel 42LRC322]

Dear All,
Thank you again for sharing your knowledge and thoughts. It is helping me a lot !

If I had a solution to reduce significantly my exhaust (at the exit) noice, I would probably do this… I have to find a specialist in Spain then.

For the pair of new JD or Beta or 6B Cummins it will cost with the new gear boxes max 40.000 euros for the 2 engines.
I have already a nearly new generator of 9,5kW Onan.
I will then end my technical refit in the 50.000 euros… I may resale my current engines for xx euros also coming in deduction.
DOes the Hatt deserve this ? Again, any newer trawler is not as strong as the Hatt or at a much more expensive like the Nordhavn.
It is a lot… but any new boat of this quality would cost above 800.000 usd no ?

 

[PierreR]

Having the same boat at the OP, I will throw another bit into the game. I calculated the correct engine for the propellers. The correct HP is 85 after transmission loss. Assuming 10% on a new gear box I calculate 94 Hp. My current dated 453's are probably only putting out about that much.
With the 125hp JD's I would be thinking about new 4 blade or wide blade 3, props as well.
I have not yet calculated the correct gear ratio as that varies per engine spec.
If I were going to do a refit for my boat, I would really be pushing the pencil to decide on the ultimate engine for propeller efficiency, economy and capital outlay.

 

[Muriel 42LRC322]

Gear boxes and propellers....

I think you to share these infos... and Yes I will have to ALSO work on this. I trust the thickness of the shafts will be at least (1,5") and I can keep them. I may have with reman Cummins 6B or 6BTs a cheaper alternative to new JD or Beta... I am waiting for all quotations at this point. What do you think I could sell my DD in working order with BW Gear Boxes ? With control panels also ??? That's an interesting point to estimate my final cost.
Thank you all again....

 

[Muriel 42LRC322]

Thank you

I thank you....

 

[Variemeh]

I'll start by introducing myself. My name is Peter and my wife and I own a 1977 Hatteras 42 LRC located in Vancouver, BC. I've been a longtime lurker...Marin likely had only about 9,000 posts when I started on Trawlerforum. I'm not positive if I've even posted before, although I have traded a couple PM's.

We rebuilt both DD 453's a few years back. We run these engines somewhere between 1,750- 1,800 for normal cruising. To correct a previous post on this thread, this is a full displacement hull, not semi (very noticeable in the ride and also Hargrave designer them as such). We are at hull speed at under 1,700 rpm but the engines seem happier at 1,800.

At 1,800 rpm they are not very loud, these are not V653's (spent lots of time listening to one!) Spinning at 2,250. Clearly they are not as quiet as newer engines though, but our rebuilt was simpler and less expensive.

That's just my opinion as an LRC owner

Peter

 

[sunchaser]

A potentially high hidden cost and associated mechanical/re-design involves dimensions. Your current 4-53 engine and transmission setup has specific LxWxH measurements along with wiring, fuel and exhaust runs.

A different engine and associated footprint will increase time, money and hassle factor. The easiest fit would be the Beta followed by the JD then the Cummins 6 cylinder. With noise and vibration reduction high on your objective list don't forget high quality motor mounts as a key ingredient.

 

[Muriel 42LRC322]

I appreciate your time and post Peter,
Also of course it is a full displacement Hull.
And then right I will have a lot of works around the engines if I was changing….
I ll see my people onboard tomorrow and the engines out.
I will décide very soon at the best option by comparing also quotations.
Thank you again…

 

[PierreR]

I'll start by introducing myself. My name is Peter and my wife and I own a 1977 Hatteras 42 LRC located in Vancouver, BC. I've been a longtime lurker...Marin likely had only about 9,000 posts when I started on Trawlerforum. I'm not positive if I've even posted before, although I have traded a couple PM's.

We rebuilt both DD 453's a few years back. We run these engines somewhere between 1,750- 1,800 for normal cruising. To correct a previous post on this thread, this is a full displacement hull, not semi (very noticeable in the ride and also Hargrave designer them as such). We are at hull speed at under 1,700 rpm but the engines seem happier at 1,800.


That's just my opinion as an LRC owner

Peter

The comment about semi displacement hull came from me, also a 42 LRC owner. I have a lot of knowledge in yacht design. If a boats speed can exceed an S/L ratio of 1.4 with some bow lift, it is a semi-displacement hull regardless of what the literature says. The S/L ratio is the boats top speed in knots divided by the square root of the water line length in feet. Hargrave designed the 42 LRC and powered the boat to hit almost 10 knots or a S/L ratio of 1.6, squarely within the semi-displacement range.

I calculated her lines from information given in the owner's manual and of course operating the boat. The boat is clearly not a full displacement boat but is also a marginal semi displacement hull. Sort of the bastard child in between. Points to a design fight with the sales department during its inception. Boats like Mainship and Grand Banks are much better semi displacement designs.
The sweet spot for the 42 LRC is right around an S/L ratio of 1.3 but quite happy at 1.2-1.4. Right where you operate the boat. If the boat was a full displacement boat, you would be right around 1.1-1.2 and think it best. In my opinion the boat was slightly overpowered to draw in marginal buyers as Hatteras was not really known for slow boats.
Bottom line: Although I would really like to believe the literature and think I had a full displacement boat, the numbers don't lie, and I don't own a full displacement Hatteras 42 LRC. By the way, it is the fastest boat over 20' that I have owned. Eye popping fast.

 

[PierreR]

Maybe I am making too many assumptions in this thread without knowing exactly how Muriel is going to use the boat. My assumptions have been concern for high gas prices and running a lot of canals with 6 mph speed limits. Maybe I am wrong, and the bulk of his cruising will be in the Med with time schedules to worry about.
In the canals, I would not want the DD's as the exhaust is loud. The DD's are back pressure sensitive and require higher rpms before the issue diminishes. To account for this the exhaust exits are above the water line until the boat reaches about 6.5 knots. I would not want to be in a mile long tunnel at 4 mph with DD's. On the plus side, no one would enter the tunnel as you could hear the DD's a half mile away at the end of the tunnel.
If canals and fuel price is the concern, repower a bit lower than the 112 Hp Detroits. If he wants to run fast much of the time then the Duty rated DD's and the JD's are the way to go. DD's like 70% power, right around 1,800 to 1,900 rpm and 8.5 knots.

 

[Muriel 42LRC322]

All clear ! I agree again then and thank you for sharing all this !
The ideal cruising speed I think is in the 8Nm... There is no point going to 10 with this hull and consumer much more.
I have a nice offer with the 6B 120hp... I could keep my BW gear boxes apparently... Would cost half of the price for new ones with recon.
I'll see my DD tomorrow at the Yard. They are ready for general overhaul.
I would have to add some weight a little bit... easy to do.

 

[rslifkin]

I have a nice offer with the 6B 120hp... I could keep my BW gear boxes apparently...

You won't be able to keep the Velvet Drives. The 6B engines will both rotate the same direction, so keeping the existing transmissions will mean you lose the counter rotating props. You'd need to change transmissions so that one prop can rotate opposite of the engine.

 

[Muriel 42LRC322]

Thank ! I told it to the Cummins rep... he is saying that the rebuilt engine will follow the same rotation I have on te gear box... So port propeller will rotate LH and and starboard will rotate RH... Your thought ?

 

[rslifkin]

Thank ! I told it to the Cummins rep... he is saying that the rebuilt engine will follow the same rotation I have on te gear box... So port propeller will rotate LH and and starboard will rotate RH... Your thought ?

I'd confirm that with Cummins, as I've never heard of a reverse rotation B series. And to get counter rotation with your current transmissions, one engine (typically starboard) will have to rotate backwards.

 

[Muriel 42LRC322]

I take note and thought so... I have to further check with him. Many thanks Peter....

 

[Nomad Willy]

PierreR is almost right .. but not.

One dosn't make a FD hull on a boat by cruising it a FD speeds.
A FD hull is a boat w the hull-form of a FD boat. It is 100% a matter of hull form. And most notably the quarter beam buttock line is the part of the question that most directly identifies the FD hullform. WO getting real technical the QBBL is the angle of the hull bottom as it rises (as one goes aft) from about amidships. This angle limits the fwd speed. The aft section/stern going over hull speed will pull the stern down and hence raise the bow.

All of this has nothing to do how fast a skipper runs his boat. It’s the hullform.

 

[Jmarsh203]

I'll start by introducing myself. My name is Peter and my wife and I own a 1977 Hatteras 42 LRC located in Vancouver, BC. I've been a longtime lurker...Marin likely had only about 9,000 posts when I started on Trawlerforum. I'm not positive if I've even posted before, although I have traded a couple PM's.

We rebuilt both DD 453's a few years back. We run these engines somewhere between 1,750- 1,800 for normal cruising. To correct a previous post on this thread, this is a full displacement hull, not semi (very noticeable in the ride and also Hargrave designer them as such). We are at hull speed at under 1,700 rpm but the engines seem happier at 1,800.

At 1,800 rpm they are not very loud, these are not V653's (spent lots of time listening to one!) Spinning at 2,250. Clearly they are not as quiet as newer engines though, but our rebuilt was simpler and less expensive.

That's just my opinion as an LRC owner

Peter

Could have swore that the brochures and jack Hargrave said the 42 lrc said the boat would do 11kts with stock engines and 240 hp overall is not much at all. also the stern was flattened specifically for not squatting while driving the hull past its hull speed which would be about 8.5kts, also no ballast, also lighter than a Grand Banks 42 which is a semi displacement boat by about 5,000 lbs, also goes as fast as the GB42 with comparable power. sounds like an average powered, average speed and average weight for its time semi displacement to me now I don’t think there is anything average about a hatteras 42 lrc at all I think it’s a very well made boat and it also has a good bit more fuel than a GB42 but don’t let salesmen bold face lie to you on something easily calculated by math and verifiable by reading a brochure and comparing to other semi displacement boats. words out of jacks mouth “it’s a true displacement”, not it’s a full displacement. Only places I’ve seen full displacement touted on a 42 lrc is owners and for sale adds. nothing wrong with a semi displacement boat at all I’m actueally quite fond of them but my Willard 36 pilothouse no matter the power isn’t getting much faster than hull speed. My Willard 36 also weighs more than a hatteras 42lrc and the Willard has I believe around 7,000 lbs added just in ballast. Also I just repowered my Willard and went with the stock engine and absolutely overpowered the boat, wish I went with about an 80hp diesel instead of a 120hp. All my extra power gets me about .5 kts over hull speed which only takes about 40hp to get to hull speed so absolutely a waste, with the engines in the hatteras 42lrc she is doing 2.5kts over hull speed. Doesn’t sound like much but it is enough to look at and say hey that’s a little too much speed for a full displacement boat and I bet with a little more power she would be even faster.

 

[Jmarsh203]

Btw I was also wrong about stating a 53 series had dry sleeves. It’s wet. And I agree with the others I’d prefer swapping out wet sleeves over dry.