Hi. I'm new to the forum as of today 8-26-2008. Will be going to the Lake Union Boat Show in Seattle in Sept. to check out some of the Seahorse Marine and planning on a visit to China in March/April to see the Seahorse factory. My preference so far is for the 462 sedan. I just love that design. So.... before going to China I'm trying to gather up as many questions and thoughts as possible so I am prepared for my trip. I have so many questions, but notice nothing has been posted on the board for over a month, so will not overwhelm everyone with a million questions. Today I would like to ask about engines and owners experiences with different power configurations. I currently sail a Hunter 38 sailboat and it can be a challenge getting into our narrow slip under certain windy conditions. With a single engine (even with the bow thruster you just don't have that much control). How about duck owners with single engines? That's going to weigh 3 times as much as my current boat. How easy are they to maneuver. I am considering going for two engines for the added control and extra power, but I don't want to sacrifice too much on fuel economy. With 2 engines I assume you can power at lower RPM's to get the same HP of a single engine at higher RPM's, but how much efficiency do you lose? Also, with Tier 2 engines, if you are powering at lower RPM's, will you damage the engine... or can you counter this by increasing power for a half hour or so at the beginning of the day and at the end of the day?

I have been researching John Deer's site on Marine engines. I have been correlating that to some of the figures I've seen about HP needed to power the 462 sedan. For example...According to Seahorse figures, at 73,144lbs 2" loading it would take 32.6 HP to achieve 8.55 Knots in calm conditions. With a single John Deer 4045T M1 engine to achieve 32.6 Knots would take aprox 1600 RPM's. Fuel usage according to John Deer under these conditions would be 2 gallons per hour. My question is, if I were to use two 4045 T engines how much efficiency would I lose. If I calculate according to John Deer's brochure, to get 16 HP out of each engine would require 1300 RPM from each engine. At 1300 RPM each engine would burn about 1 gallon per hour, so it seems the fuel economy would be the same. Does this sound right.

Anyway, thanks in advance for answering my first question. Take your time, I'm in no rush.

Michael

umiak is the Sedan that will be at the show. It is the only completed one, and will be for sometime. I'd guess the next ones have a year to go.

I agree with Don there aren't a lot of benefits to increasing the power of the engines on these boats. Once you hit displacement speeds more hp doesn't buy much more than higher fuel consumption. In respect to heading into bad weather it is often better to slow down as Don mentions.

For the Duck the JD does fit better as the engine room is much shorter. For the Sedan it doesn't matter as the engine room is probably almost twice as long.

A stern thruster is not needed and as Don mentions not an option. If you want better control of the the stern at slow speeds an articulated rudder would be a better option. The yard might do this if the client provided the rudder to meet the stock opening. However, it really isn't needed.

Hugh

Hugh

Well if you put the 6 cylinder engine in you will loose some engine room space!!...but the real issue is the hull of the DD462....with my JD 135 turbo etc I have more than enough power when it is calm if I want to go faster...up to 9kt...and sure we slow up as the wind and waves get bigger but that is just fine because the ride can get crazy If you had unlimited power to keep boat speed at 9kts..or 8.5 kts...and you would be using lots more fuel...but the real decider is how the boat handles and rides in the conditions...and what the people onboard are going through...think about it...do you really want to go faster because the waves have got up and the wind is now 28kts on the nose??...Hang on for the ride!...you can have a car with huge HP but if the road is rough you have to slow the car right...well that is the same with any boat...especially a full displacement one....you get to a point where you have just the right amount of power...not too little , not too much...just right, so you can always run the engine at max tourque and it sort of matches the hull shape/displacement/waterline length etc...DD have a tugboat bow which I like, good boyancy but no flare so it cuts the wave, less spray into the air and no sudden jump up so better ride....and for the DD462 my JD is just right.....you need to think about the reasons you may want to power up to go faster and what type of sea you are likely to be in...usually there is nothing to be gained?? that's assuming you want a DD...obviously all this is blown out the door if you just want to do 12kts in flat water no wind up the river...but then you are looking at the wrong type of boat...DD are full displacement...they are a long distance ocean voyaging trawler at 7kt, a coastal cruiser at 8kt and if you have to get somewhere in a hurry and the weather lets you try 9kt...all on less than 140hp...the standard SHM motors are OK...But I still like the JD...and the sizes are right.

Another thing to remember is that ICE was the last fully custom DD that SHM will ever build...they are now very much "PRODUCTION BUILDERS" as they are so busy, that is the only way they can keep up...so when you talk to them you will get a list of standard specs...very comprehensive...Which will be the ONLY ENGINES THEY FIT and a list of factory options...NO STERN THRUSTER?... to be decided at the time of ordering and before signing the contract...then that is it...Prices seem OK on the options compared to some of the extra charges back in the days of custom builds...so order ALL the extras at the begining and you will get extra savings...

Forget the stern thruster....you will not need it...you will use the prop thrust/rudder as your stern thruster....Believe me..it works....think of the money you will save....

Good luck...

Don and Hugh:


Thanks for the responses so far. Just a few questions based on what you guys have said so far. I agree about the 2 engine option is not the way to go (and if SHM does not offer, then that question is settled). As far as size of engine though, why would you not want to go any larger than 135HP? Do you find that the fuel economy suffers a great deal with any larger engine on this particular boat. It would just be nice to be able to power up if I need it to get somewhere quicker. I'm sure most of the time I would not want to do that, but you never know. Is the speed increase really not going to make the larger engine worth it? I was thinking along the lines of the John Deer 6068 Engine rated at 158 HP

Also, is the fact that you don't want a stern thruster a cost factor, or does it really not provide that much more control than a bow thruster alone.

Hugh, is it Umiak that will be at the Seattle Boat Show starting September 10? I'm flying in from New Jersey for the sole purpose of seeing this particular boat. I would love to speak with you if you are there.

Thanks Guys,

Michael

Hi...No the prop seams really good...for awhile I thought I could do with a slightly bigger pitch as I maxed out reasonably easy but when I am doing 9.2kts you push so much water it is no Joke ....I organized my own Stainless prop from Michigan on their recommendation for sizes....and it is good...then Fido gave me another exactly the same in Bronze for the SHM prop which was really good of them...so latter - one day....I may push the pitch on the bronze prop a little and try it out just for fun??

Never had any singing at all....but the blade shape is very broad-thick and quite a large surface area....

You made some Good comments about engine choice...I agree with everything but still happy to go with John Deere as it is a strong name in the Trawler market which may help resale...But rest assured I will be keeping ICE for a very long time....Just sounds nice saying "John Deere" when asked!

quote:

Originally posted by DD462-6 ICE Don & Margie McIntyre:

Using a 30 x 20 4 Blade Michigan workboat Prop and 3-1 Twin Disc gear box,

Don,

Do you have any prop sing issues with your propeller? I have a 3 blade Mikado with a slight amount of sing from 1,200 to 1,700 rpm. Cruising rpm on the IVECO should be in the 1,500 to 1,900 range so I'm planning to pull this propeller and keep it as a spare.

Hugh

I agree that the engine is properly sized and that a larger bow thruster or stern thruster is not needed. (Don has a lot more experience with this boat in heavy weather than I do so my comments are limited to more moderate conditions.)

Twin engines wouldn't be an improvement and I doubt the yard would do it anyway.

I would not reccomend the lugger engine as you don't get a good increase in reliability and/or performance over the John Deere or IVECO for the substantial extra cost. Most of the mechanics with whom I've spoken with seem to agree, though like most systems on boats I'm sure there is more than enough room for debate.

Personally, I wanted the engine as simple as possible so I choose to keep the NA, mechanical governor on the IVECO as the JD NA engine does not meet Tier II requiments and the IVECO does. The IVECO just has less stuff to break than you have on the John Deere. Being normally aspirated they also run under much less demanding conditions. Having said that the JD is a very reliable engine so it isn't worth worrying too much when choosing between the two.

The only real negative on the IVECO is they just don't have the worldwide service network that you will find with other engines. This is more an issue with warranty work than general repairs, as these engines are built on the same line as the cummins so just about any half way decent mechanic can work on them. (for people that aren't familiar with IVECO Fiat builds these engines, builds a ton of them and has for some time. The Fiat factory that builds the IVECO also builds Cummins diesel engines.)
Granted John Deere and Lugger are wet cylinder engines so eventual rebuilds are somewhat simpler, but you can put such a huge amount of hours on these engines before they need rebuilds that I'm not sure that really matters. I would also expect the turbo engines to need to be rebuilt sooner than NA engines based on higher cylinder pressures and rpm they run at.

In short all the engine options offered by the yard are well sized, well built and reliable. You will be fine with whatever engine you choose.

Hugh

Well you are on the right track doing all your research now and it is a bit daunting shifting up to a heavy Trawler like the DD462...but they are great boats. Having spent a little time playing around with ICE I can say that SHM have the right size Bow thruster for most situations....I have the JohnDeere 135 turbo and it is the perfect compromise on HP/Fuel/Revs etc. I would not want any bigger engine...I call ICE a 7kt boat for most planning which gets pushed up or down by wind and waves, but in Flat water with no wind I get 9kt plus at 2500rpm and an easy 7kt and a "bit" at 1800rpm, the Max Torque pos. and use 2 and a "Bit" gall an hour.

Using a 30 x 20 4 Blade Michigan workboat Prop and 3-1 Twin Disc gear box, we get pleanty of low down Kick for close manouvering with the bow thruster and do NOT need a stern thruster or twin engines. It is easy to do on the spot 360 turns...only took a day of play to work out the handling of the 462 and it is great! we have slightly increased the size of our rudder adding a small fin on the top of the standard SHM rudder.

I would forget completely about twin engines or a stern thruster...nothing against IVECO...but go with a Lugger or the John Deere....and spend your money saved on the other extras if you order from SHM like Selftailing winches....good luck...they are great boats.

One additional thought. Would a good Bow and Stern Thruster instead of the second engine give me the control I need. Maybe my current bow thruster is just undersized as it has little effect. Thanks.