Dream Engines

Discussion in 'Powerboats' started by Portager, Jun 26, 2002.

  1. John Capuano
    Joined: Feb 2004
    Posts: 14
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: PORTLAND OR.

    John Capuano Junior Member

    HI! Its taking some time to digest all the good info from everyone.Iam about half way through understanding it all. While I chew on the info I already have,I thought I'd relay some info and ask a few more qestions.I found a Lugger,smallest I could, for my side engine model L984D power output 70HP. Can't find out if wet or dry liners.Does any one know? Is this the smallest Lugger available? Lastly,if I understand Portager correctly,my gen would be run from a PTO shaft off my engines. Does that mean that the gen will only recharge my batteries when the engines are running? Can a gen be both a PTO driven and have it's own internal engine to make it run if both engines are down? I know this may seem silly, but the more layers of back-up the better as far as I'am concerned.Thanks.Don't rush your reply,I've got plenty to chew on! Oh,I found the Fabco PTO gen on the web,they look first class and best of all never need adjustment for different engine RPM's.
  2. Portager
    Joined: May 2002
    Posts: 418
    Likes: 13, Points: 0, Legacy Rep: 325
    Location: Southern California

    Portager Senior Member

    I believe the L984D is the smallest Lugger propulsion engine available. I can’t find any reference to cylinder liners for the L984D, so I don’t think it has any. Since it is based on a Toyota block as opposed to most of Luggers, which are based on John Deere blocks, I think it is probably a throw-away. If you would prefer cylinder liners, you might consider the Lugger LP445D. The LP445D has wet cylinder liners and it is rated at 85 HP maximum, but the continuous rating is 65 HP @ 2200 RPM. I provided a comparison of the differences between the L984D and the LP445D:

    Specifications: L984D LP445D
    Bore: 3.85 in (98 mm) 4.19 in (106 mm)
    Stroke: 4.5 in (115 mm) 5.0 in (127 mm)
    Displacement: 212 cid (3.47 ltr) 276 cid (4.5 ltr)
    Length: 46.22 in (1174 mm) 45 in (1143 mm)
    Width: 25.15 in (638.7 mm) 24.6 in (625 mm)
    Height: 27.27 in (693 mm) 35.3 in (896.3 mm)
    Weight: 787 lbs (357 kg) 1070 lbs (485 kg)
    With Hurth gear Keel Cooled, without gear
    Continuous Duty: 64 HP @ 2200 rpm 65 HP @ 2200 rpm
    Low speed ~29 HP @ 1000 rpm ~29 HP @ 1000 rpm

    As you can see the LP445D has 30% higher displacement and 36% higher weight (without gear-box), but the power is about equal and longevity should be better.

    Close, but on the L984D & LP445D, the PTO power level is limited to 5 HP, which would only power ~2.5 KW generator. What I’m recommending is a large hydraulic pump coupled directly to the main shaft of the auxiliary.

    On the main engine, the pump could either be located between the engine and the reduction gears (note with a controllable pitch propeller you do not need a reversing gear) or between the gear-box and the main propeller shaft. Either way, this requires a pump/motor with “drive-through” shaft. Putting the hydraulic pump between the engine and the gear-box allows it to operate at higher RPM and therefore requires lower displacement. Additionally, the pump/motor on the auxiliary and the one on the main can be identical, which means interchangeable parts and fewer on-board spares. When the main engine is running, the pump can provide sufficient power to run all the hydraulic systems.

    I’m not sure I understand this question. A conventional generator has an engine coupled directly to a generator. The generator does not produce power unless this engine is running. With the system that I’m proposing, the generator can produce power when either engine is running. If you’re referring charging to the engine starter batteries, I plan to keep a separate alternator and battery to operate the starter. Why mess with success?

    Redundancy is a good thing, but only if applied intelligently. The classic example is the twin engine aircraft, if it can’t take off on a single engine (and most can’t), then having the second engine only makes it more likely to have catastrophic engine problems on take-off.

    The simple answer to your question is yes, you could have an additional engine that is connected by an electric clutch or even another hydraulic pump, but the real question is would that give you the additional security that you desire? That answer is not really, because your fixing the wrong problem.

    The truth is having two separate engines fail due to independent causes is extremely improbable. It is the common causes that you need to worry about. On Diesel engines, the most common cause of engine failure is bad fuel and if you feed your engines from a common tank, or buy all your fuel at the same place, or transfer fuel from one tank to the other, well you get the point. The common denominator for the hydraulic systems is the hydraulics. Hydraulic systems are intrinsically very durable, but a leak can allow the critical fluid to escape and shut the whole system down. It is important to have isolation valves to shut off branches that develop problems. It is also important to have spares onboard and enough hydraulic fluid to refill the system once or twice, but the same is true for any drive approach.

    Mike Schooley
  3. John Capuano
    Joined: Feb 2004
    Posts: 14
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: PORTLAND OR.

    John Capuano Junior Member

    Thanks Portager! The 85 HP Lugger engine sounds good. Do you know whether that is the true HP? What would it be at approximately 2200 rpms? Am I going to have a problem with hydraulics because I'm over the 50 HP rating? Next, the problem with the power generator coming off the PTO takeoff is the following: when I'm at anchor in a remote location for several weeks at a time I would have to run the engines several hours to recharge the batteries since diesel engines don't like to sit and idle I would have to pull up anchor and run several hours then return and drop anchor - this seems inconvenient at best. I would like to have a separate generator for the air conditioning equipment but I'm thinking of another generator to recharge the batteries and for general power usage. I thought of using solar panels as one way of recharging the batteries without having to get "underway". Would you know of a good generator that is easily rebuilt and not coupled to the engines. I'm still open to your suggestion if we can get around the problem of recharging the batteries without having to get underway. Next, it has come to my attention that having "clean" power for all the electronic equipment on board is necessary. Anyone have any thoughts about this? Lastly, is the problem of getting power while at dock in a marina. Europe is 220 volt, 50 cycle - USA is 110 volt, 60 cycle. I assume two separate exterior plug systems tied to two different inverters will be necessary so that I can run in either Europe or the US. I still haven't decided to wire the boat mainly for use in the US or Europe. Thanks again to all who have contributed. I look forward to your comments. P.S. I have been told that it would be best to wire the boat to NMEA 2000 standards -which is better for component compatability rather than NMEA 0183 which seems to be the standard most boats are wired to today. Any thoughts?
  4. yipster
    Joined: Oct 2002
    Posts: 3,486
    Likes: 96, Points: 58, Legacy Rep: 1148
    Location: netherlands

    yipster designer

    have a quik link to some info on the new? NMEA 2000 standard?
    we use NMEA 0183 and to a laptop interface with a RS 232C convertor for plotter, autopilot. i hear about "clean power for all the electronic equipment" just never found that need, all works fine on 12v. only problem insatalling GPS was that the singnal out was not working off factory (in "95). do have somewhere an old floppy to test this circuit, i try to dig it up and post it here, when needed it can be very handy!
  5. Portager
    Joined: May 2002
    Posts: 418
    Likes: 13, Points: 0, Legacy Rep: 325
    Location: Southern California

    Portager Senior Member

    Continuous Duty power rating @ 2200 rpm is 65 HP.

    No, 50 HP was only a guess and 65 HP is close enough. Besides you could use a 50 HP pump if that was all you wanted. You would just need to run the engine slower (i.e. it produces 50 HP at ~1950(?) rpm.

    First the statement that diesels do not like to sit and idle is only true if the engine is under-loaded. Engine manufacturers publish the optimum power output versus engine speed curve for their engine. You can operate the engine anywhere on this curve, but they should not be operated more than 50% below the curve. The confusion in this area is due to fixed pitch propellers, since the propeller power demand curve does not follow the engines power production versus speed curve, the engine is always under-loaded at low speeds. This is where the controllable pitch propeller is useful. By controlling the pitch of the propeller you can keep the engine on the ideal load curve. The hydraulic/auxiliary is similar to the controller pitch propeller. By using a variable displacement hydraulic pump the power demand of the pump can be adjusted to the ideal power output curve of the engine allowing the engine speed to adjust the power demand of the ship.

    To recharge the battery bank, I advocate hydraulic motors to power high output alternators. I plan to use two alternators that produce 200 amps each at 24 VDC which equates to 9,600 KW of DC power. This will recharge a 1000 amp-hr battery bank from 50% to 80% in about 1.5 hours with the engine running slightly above idle. If the AC generator is required while the alternators are charging the battery bank, the auxiliary engine can run them both by slightly increasing engine speed.

    The beauty of the hydraulic system is it allows the auxiliary engine to provide the ability of both a small generator and a large generator and also provide back-up propulsion.

    There are two types of power used on boats, AC power and DC. The best source of “clean” AC power is a true sine way Inverter. Engine driven generators are prone to frequency and voltage surges, which can damage sensitive electronics. The best source of clean DC power is a DC to DC converter; although most DC equipment has a high enough input voltage range to run off the battery bank.

    My plan is as follows. Maximize use of components that run on DC. Provide a battery charger with that accepts 50 or 60 Hz AC. Put most 60 Hz AC loads, like microwave ovens and coffee pots on inverters. The remaining AC systems consist of resistance heating elements and items that are hard to run of inverters. The resistance heating elements can use either 50 or 60 Hz. For air conditioning, I’ll use systems that can run on 50 or 60 Hz, such as Cruisair air-conditioners. I’ll wire my AC system for 220 to 240 VAC and have a step-up transformer to convert 110 VAC to 220 VAC and separate shore power connector. Here is a link that describes how Nordhavn deals with this problem http://www.nordhavn.com/atw/underway/forums/forums_bobaustin1.htm .

    Mike Schooley
  6. Gypsy72
    Joined: Mar 2004
    Posts: 9
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: Naples, FL

    Gypsy72 Junior Member

    You cant go wrong with the 71 series, simplicity at its best, and an impressive growl to boot!
    Now your talking my language........dont get me wrong, Yanmar has an impressive line up, Cummins has always chugged along with Cat in the marine end, and Volvo is, well I'm not very found of Volvo, but Detroit has always been the noisy, messy, smokey, loud, powerhouse of choice for me.
    But my "Dream" engine is the Fairbank Morse, opposing 10cyl.
    My first expierince with diesel was standing between two of the behemuths and lite off and I was hooked.
  7. brian eiland
    Joined: Jun 2002
    Posts: 4,964
    Likes: 188, Points: 73, Legacy Rep: 1903
    Location: St Augustine Fl, Thailand

    brian eiland Senior Member

    Gardner engines

    I remember hearing only good things about these engines. I believe the 'BlueBird of Thorne" had one of the 4 cyl models.

    Do they still build engines? or have they been bought out??

    Isn't the Inline 6 cyl configuration the most inherit naturally balanced configuration of those internal combustion engines we utilize today??....requiring the least counterbalancing on the crank shaft,etc.
  8. pungolee
    Joined: Jun 2004
    Posts: 103
    Likes: 1, Points: 0, Legacy Rep: 34
    Location: north carolina

    pungolee Senior Member

    dream engine(s)

    My dream is a pair of matched 1955 Johnson rde-17 25 hp electric start outboards, with OEM hardware.Bronze transom protectors would be nice.
  9. paul wilkins

    paul wilkins Guest

    I am looking forone or two hurth transmissions HSW630A 2:1.
  10. Tommygator

    Tommygator Guest

    LUGGER and other engines

    I noticed that someone stated that lugger used john deere blocks. this isn't always the case. they actually use very few blocks by deere. they started that way, but once the engines became popular, they switched to some others, i believe ISM, Komatsu and or toyota diesels are the base. Check into IVECO engines for fuel efficient, powerfuel for size engines that don't have the high RPM of VOLVO or YANMAR.
    ALso, a hydraulic drive to the prop shaft has been used as a combiner. with 2 diesels running to one motor, as in a hydrostatic drive. but why?



    Joined: Oct 2002
    Posts: 4,519
    Likes: 110, Points: 63, Legacy Rep: 1009
    Location: Conn in summers , Ortona FL in winter , with big d

    FAST FRED Senior Member

    "By controlling the pitch of the propeller you can keep the engine on the ideal load curve. "

    Not usually , the DIAMETER of the prop is the largest load ,
    the pitch merly helps efficency.

    To TRUELY load an engine at low rpm
    (without the yet to be invented Variable DIAMETER prop)
    a multi speed transmission would be cheapest , most efficent choice.

    An EGT gage would be required.

Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.