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  #1  
Old 07-08-2010, 11:41 PM
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Boston Boston is online now
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Most economical diesel

Hi again folks
most of you know what Im up to
so now its time to pick an engine

I know the boat
an Atkins Great Bear
15000 disp
38'
displacement V hull



thing calls for a 70 hp diesel

ok so which 70 hp diesel

my requirements are that it be common
downright boring actually its so common
the kind of thing where if you mentioned the engine type any farm kid would say "**** we had one of those out on the back 40 we used for parts on the new one we bought just last year"
most common diesel in the 70 hp range ever made is what I'm after

next trick is to find a 2:1 reduction geared transmission with revers
now Im thinking the same tractor motor will also have this gearing for the tractor cause I've driven enough of them to know the new transmissions are clutchless and you simply throw a lever just like in the marine applications

so why let some fool stick the word marine in front of it and quadruple the price
the ranch wouldn't pay that much for it so why should I
its the same engine

dry exhaust
Im going to be in Alaska kids so why have through hulls that might freeze up on me and sink my dream before I even make it through that first winter

radiator
Alaska need I say more
run the coolant through the hand rail if I dont need the heat inside
keeps my fingers happy when Im fishing

tranny
something ultra simple and not specific to marine use
add the word marine to anything and quadruple the price
sorry but not happening
Bart's farm and supply is just as likely to have the parts I need as the specialty marine shop and at 1/10 the price

maybe tomorrow I'll call the boys in my old home town who run the tractor repair place and get the skinny from them on what I should be aiming for but untill then I thought I'd just create a new thread and throw the question to the group and see if anyone else went down this road in an effort to find some sanity to the cost of "marine" engines
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Old 07-09-2010, 01:22 AM
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[quote=Boston

Alaska need I say more
run the coolant through the hand rail if I dont need the heat inside
keeps my fingers happy when Im fishing
[/QUOTE]

Cripes,-- Boston you may have stumbled onto a cracking idea there.

I would seriously give that some thought.
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Old 07-09-2010, 01:34 AM
Brian@BNE Brian@BNE is offline
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If still talking tractor diesels then my guess its a John Deere model. I saw stats. saying they've been market leaders in UK for over a decade, and although its quite a while since I was on the farm, JD are have likely been the leaders in Australia for a long time also. Well deserved reputation for quality, but spare parts seemed quite expensive. Premium product but with premium pricing? Could even get close to 'marine' pricing? Case IH might be cheaper, but not that many units sold in this part of the world, in recent years at least.

For farm trucks, way back when gas was cheap they mostly had gas engines. When diesels started making inroads, Cummins was first choice but Perkins had lots of units in both tractors and trucks and were highly regarded here.
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Old 07-09-2010, 01:34 AM
powerabout powerabout is offline
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sounds like you need a
hand cranked
air cooled
direct reverser
dont think they get simpler than that
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Old 07-09-2010, 05:11 AM
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There are three or four older guys who do nothing but tinker with old tractors in my old home town. The place they work is like a country icon of tractor lore. Im betting they would have it down in a heartbeat.

Brian Im glad you posted the pict of that sail drive over on the other thread

the drive leg
Im betting that thing swivels and would be perfect for what I have in mind for my no through hull drive system. I'll have to make a sketch of what I think I want so far and present it cause Fanny and I have discussed a type of drive that if it strikes something can pivot up and slide over the obstacle without damaging the prop. That and the vertical drive shaft allows for a much safer penetration of the water surface with the mechanical IE no stuffing box to malfunction or at least one with limited potential to sink you boat if left untended

The drive mechanics is one thing Im still hoping to get creative with and produce something that works best in an area that is known for obstacles
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Old 07-09-2010, 06:08 AM
FAST FRED FAST FRED is offline
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Location: Conn in summers , Ortona FL in winter , with big dock & room for O'nite stop .
A Deere is a good choice , simply see the Tractor guys and forget the marine folks. Deere usually has a "sale" or two a year where a factory rebuilt can be had with NO Trade in.

It might be cheaper to simply purchase a used tractor and canabalize.

"something ultra simple and not specific to marine use
add the word marine to anything and quadruple the price
sorry but not happening "

Wrong concept , a marine tranny has a built in thrust bearing that would be hard to do with out it being built in.

Used Twin Disc , or rebuilt are great . The best of the lot of TD came from WWII landing craft. Usually in the $500 range , but heavy to ship, So robust they can be shifted from Fwd to reverse at full tilt, 200hp rated, uses SAE 1 bellhousing. usually 2-1 but other reductions are out there 1.5-1 and 3-1

Can be run in reverse on a cont basis , so you can have the shaft direction you prefer for stern walking while docking.
And find more common used props.AHOY in LA is best if you want a new prop.

Mechanical gear operation (lever) so lots less to buy install maintain.

Simple pipe keel cooler will take care of all THE ENGINE COOLING needs.

I would consider a bunch of bus box heaters (found under the seats on skool buses) to heat the interior.

A non marine engine is a fine concept , a non marine tranny is a poor choice.

Look here , http://www.boats-and-harbors.com/classifieds.cfm to find realistic pricing of used engines and trannys , and anyhing else you might need.

IF the boat can take the weight a DD 3-71 would be cheaper to install, but makes 16 hp from each gal of diesel, a 4 stroke Deere might make 18 hp, so it will depend on the boats use.

Thousands of hours a year the Deere might pay , only a few hundred the cheaper DD would be fine




FF
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Old 07-09-2010, 06:36 AM
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exelant stuff Fred so I need to go through it point by point and make sure I have it all straight

Quote:
Originally Posted by FAST FRED View Post
A Deere is a good choice , simply see the Tractor guys and forget the marine folks. Deere usually has a "sale" or two a year where a factory rebuilt can be had with NO Trade in.

It might be cheaper to simply purchase a used tractor and canabalize.

yup
I was thinking of buying a factory rebuilt or even new if I could get it once I finalize the decision


"something ultra simple and not specific to marine use
add the word marine to anything and quadruple the price
sorry but not happening "

Wrong concept , a marine tranny has a built in thrust bearing that would be hard to do with out it being built in.

I am working out a system similar to the one Fanny and I discussed over on the Boats n Stuff site that I will introduce soon as I get some sketches done, but the concept is that the drive needs to be able to slip up and over obstacles like ice or deadheads in the water. which means that the thrust is not directly applied to the engine per se but instead it is directly applied to a thrust plate on the hull.
The inside passage is known for having lots of floating debris and this system if I can make it work might just catch on. Course it might also end up being nothing but a headache if Im not careful and do some tinkering before I finalize the design.



Used Twin Disc , or rebuilt are great . The best of the lot of TD came from WWII landing craft. Usually in the $500 range , but heavy to ship, So robust they can be shifted from Fwd to reverse at full tilt, 200hp rated, uses SAE 1 bellhousing. usually 2-1 but other reductions are out there 1.5-1 and 3-1

Can be run in reverse on a cont basis , so you can have the shaft direction you prefer for stern walking while docking.
And find more common used props.AHOY in LA is best if you want a new prop.

Mechanical gear operation (lever) so lots less to buy install maintain.

sounds like what I want in terms of trany I'll have to look into it

Simple pipe keel cooler will take care of all THE ENGINE COOLING needs.

I dont want through hulls nor do I want exposed pipes under the hull that might be damaged by ice or on the rocky shores of the PNW

I would consider a bunch of bus box heaters (found under the seats on skool buses) to heat the interior.

:-)

A non marine engine is a fine concept , a non marine tranny is a poor choice.

Look here , http://www.boats-and-harbors.com/classifieds.cfm to find realistic pricing of used engines and trannys , and anyhing else you might need.

IF the boat can take the weight a DD 3-71 would be cheaper to install, but makes 16 hp from each gal of diesel, a 4 stroke Deere might make 18 hp, so it will depend on the boats use.

Thousands of hours a year the Deere might pay , only a few hundred the cheaper DD would be fine




FF
great stuff Fred thanks
B

oh
I plan to do some exploring so I'll likely be under power quite a bit or at least till I get fishing guides
which would be kinda nice but not essential to the overall plan

cheers
B
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  #8  
Old 07-09-2010, 06:44 AM
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Consider air-cooled, Bos. No schoolbus heaters if you do choose a water-cooled diesel - use a big radiator to transfer much more heat. My prefence is a conventional shaft rather than any funky pop-up unit, I/O, or anything else. Single engine with a deep keel with a steel shoe for the length of it will prevent anything from hitting your drive. Please don't fret about a drip of water coming in (but DO use a conventional packing gland with one of the new, fancy, teflon packing materials - I never wud have believed it but I havn't pumped out a gallon in a year with a perfect shaft and fancy packing. It's weird stuff - there is a little heat being generated but it seems to dissipate before getting hot and doesn't burn like too tight waxed flax wud. I'm going to replace prophylactically this fall. I guess it wud be dangerous to positively pressurize the engine compartment and let the hot air warm the cabin (remember the Corvair) but I'd do it anyway with carbon monoxide, whatever-fumes-diesels-produce detector in case of exhaust leak. There is not a nickle's worth of difference in diesel economy. Base your desision on torque, RPM, parts, service, etc.. John Deere are pretty good but having dealt with big marine engine companies (Cat, Volvo) all my life (oh yeah, that's part # 123xyz - it'll be here tomorrow), it is a different world when you go into Cascade (who you wud be dealing with) and talk about a PTO for your new engine and they say "Huh?" Here is an engine that is so simple and reliable that you won't need a mechanic: http://www.staufferdiesel.com/s102v0...ec%20sheet.pdf Think slow, think low power, live long.
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Old 07-09-2010, 06:55 AM
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thanks Mark
hows things, haven't heard from you in a while. Ill definitely look into that motor but for now I have to get to work, found a great job by the way and whats really nice is its just the nicest group of people you could ever ask for. Great crew and fantastic upper management possibilities, hell I just wrote the policy and action plan for the new department I seem to have landed in charge of.

Anyway you definitely have the picture of what I want, something that is not turbo charged though, normally aspirated and operates best in the 1500 rpm range or lower, supper common and I dont really care how compact it is, what I really want is ease of service and fewest peripheral gadgets which the Air cooled option definitely offers

thanks again folks
Im getting some really great input
B

turbo's might reduce noise and add a bit of power but I've got a non turbo diesel now and its cake to work on and there's just not much to go wrong when you have no fancy stuff involved

Im open to the option but you guys are going to have to convince me a bit before I'd really consider it
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Old 07-09-2010, 07:23 AM
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Glad you got a job. I have never seen this before but there are couple of hobos here in tough shape. I was talking with an associate at a local hotel the other afternoon and a guy was pert-near crying looking for work. I was just about to offer him a made-up job and he started to get creepy so I didn't but the incident was an eye-opener. I'm fine, tourism is a little down, Europe is the new Japan (no money for vacations/bad exchange rate/EU restrictions on shipping fish) but Mexico, US, Canada are pretty strong. Met a guy from NZ who just rode eight thousand miles on his Harley (there was a race from Florida to here) and is planning eight more...and loves it so much he is going to move here - I told him we shud just trade houses!
Turbos are very reliable - not until you get into air coolers (inter/after) does reliability really suffer. Of course, simple is good and lives long. If there's anything you can do to make the engine space larger and more comfortable, I wud do it. Have a tool/work bench even if you have to sit down to work there - don't just bury your tools in a bucket or drawers. One of these makes life nice; http://www.xantrex.com/web/id/302/p/1/pt/7/product.asp - I wudn't be without. Coffee, toaster oven, computer, vacuum, everything!
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  #11  
Old 07-09-2010, 08:42 AM
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The Deere 4045 is a proven choice in that ballpark.
http://www.deere.com/en_US/rg/ESC/Sp...0_A_S0_R0.html

And instead of the Xantrex I would go for the Victron power management if need be.
http://www.victronenergy.com/

my 2c.

Richard
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Old 07-09-2010, 12:02 PM
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It so happens that I just sold my Xantrex and ordered a new one (I do this sort of thing every few years instead of waiting for things to quit). I could stop my order and get a Victron if you think they are much better...Shud I?
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Old 07-09-2010, 05:30 PM
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Quote:
Originally Posted by mark775 View Post
It so happens that I just sold my Xantrex and ordered a new one (I do this sort of thing every few years instead of waiting for things to quit). I could stop my order and get a Victron if you think they are much better...Shud I?
I would do so, yes.

Follow the link, study the recommendations, all solid and professional done. We doŽnt install others since about 4 years now. For good reason....

Regards
Richard
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Old 07-09-2010, 05:36 PM
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I trust your professional opinion. Thanks
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Old 07-09-2010, 05:46 PM
Carteret Carteret is offline
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I agree with the 4 cylinder Deere 4045. It is an excellent engine.
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