looking for advise

hey fellow boat builders,
im new to this forum but i have read numerous postings, comments, etc I have done countless hours of research and decided on my first project a 20' to 24' cc boat with a small diesel motor speed is not as important to me as fuel mileage and reliability I am a die hard fisherman so I have certain requirements 2 50 gallon live wells and lots of room fish boxes and lots of fuel for long days of trolling and or hunting fish I live in new England so I fish rivers open water and close into rocks one of the questions I have is gear ratio and or speed conversion I am a mechanic by trade and understand automotive drive trains but I am a little lost on the this motor speed and hp makes this boat go this fast I neeeeeddd the math. anybody who can recommend a good book or web page explaining the math to me that would be great. next I would like some opinions on clarkcrAFT boat kits . I have been looking at the Viking 22' cc kit if anyone has built one of these please let me know a few things like in board engine capacity how it preforms in rough water, shallow water or any other kits for the same size boat. other then the motor I troll a lot I have limited knowledge of boat transmissions but I have read numerous pages on hydraulic trolling valves/transmissions any in site on these will help me make a great choice

 

Hi Slo,
You need to visit boatdiesel.com for details on power/drive train design and construction. They provide calculators to help you decide horsepower, transmission, shaft size, propellor, etc, and how-to articles on installation and other related topics. It costs $25 to get in for a year, but is well worth the bucks. The prop calculator alone is worth its weight in gold, as it also provides fuel burn and speed numbers.
Add all that to the info you can get here, and you have the basis to build the boat of your dreams.
good luck and tight lines!

 

thanks kapn d i have seen the site and i was hoping to get some feedback on that site before i spent the money you just saved me a posting thanks and $25 for information is cheap cheap

 

I complained exactly twice (in a polite way) about how hard it was to navigate & use the forum, The guy threw me off. lots of good info there for sure.
I 'm liking what I'm reading about the Mercruiser 4 cyl. diesels. Maybe reconcider the new 2 stroke EFI outboards, They sip fuel as good as anything.
Metal Boat Society is another good hang out spot

 

hey thanks ted i have done some serios reserch on the merc diesels and im not convinced they are what they say they are in the automotive world the proff is in the pudding show me dont tell me kinda stuff i have been flipping around the idea of converting a briggs and statton diesel mot to work in my boat if you like i can send you some information on what i have found

 

A Briggs diesel? I'm not aware @ all.

 

the vangard series offers a few small engines ranging from 23 to 31 hp they use them on many generators and should be eaisly converted to a fresh water cooled sytem with a heat exchanger these are extremly reliable engines i have worked on them many times mostly pm and can turn out over 50 bph with very little time or funds northertool has them listed for about 4000 there are a lot cheaper places to get them i was considering these back when i wanted to build a 15 foot bay boat but call it foot fever or the quest for bigger fish by the way the vangaurds are very light easy to work on and parts are over the counter cheap in the future i might still convert one for a small boat i have one now that i paid next to nothing for that had water inthe filter and the guy wanted to go back to a gas motor i was lucky i had a small gas motor to trade him and i got the job to boot i went though the motor top to bottom and made some imporvments like coating the pistons better rings better injectors and better head gaskets also coating of the rod and main bearings i am looking now for the sites with the specs and for a few other things i can send you on them

 

http://www.commercialpower.com/display/router.asp?DocID=79677 here is the link to the vangaurd site

 

to power my new cc boat i am looking at the beta 90 bhp engine i would really like to run a i/o set up just for the versitilty again i am not up to par on the specifice of the drive line yet but i understand i/o have lots of failier problems to me this can be fixed with some simple things < coating the gears with dry film coating the same ones we use on the gears of in the transmissions in my race cars also cryogenic hardning of all internal parts proper tolerances and good lubrication it works on the track i can only assume it will do the same on the water my goal is relieabilty the more time i have to spend fixing my boat the less time i can fish i havent spent a single penny on my dream boat yet but i have countless hours into reserch other then the drive train but im getting there quick i learned a good lesson on the water off of block island in 6 foot seas few years back in a 34 foot boat single engine boat the sound of a deisel motor running out off fuel from the fly bridge to the deck in less then a second as we hurled in a very strong current toward the rocks motors wont start hatches up getting thrown around like a rag doll looking for tools trying to figure out what went wrong the very inexperianced boat owner i was fishing with said "tools why would i bring tools its a new boat " a pair of pliers from a tackle box was all i had but it was enought to crack the fuel line to see if we were getting fuel guess what no fuel i looked up and seen the rocks comeing quick and thougth this isnt gona be good i cut the fuel line back about 2 feet and sucked on the hose to see if i could get fuel out of it sure as sand i did bad fuel pump i grabbed the wash down hose and cut off the end and fed it into the tank and grabbed a bucket and siphoned fuel into it a soda bottle in line with duct tape to pump it into the fuel line dangling off the motor a panicing capt finnaly calmed down enough to hit the starter and the motor came to life after a quick bleed of the injectors i looked up as he put the boat in gear and less then 50 yards seperated us and the rocks i learned two things that day as i sat in the emergancy room after a 4 hour hell ride home getting stiches in my head arm and realing the sickness of swollowing fuel first thing i learned is i dont trust anyone to build anything that my life depends on the other ask the capt important things like where is the tool box, life vests,and hows the upkeep on the boat

 

Slo Troll,
There are many great marine propulsion products already on the market, tried and true, and I find it hard to believe that you will be able to improve on their millions invested in R & D with your "havent invested a cent" farm catalog approach. Do you run a Briggs & Stratton or a Mercruiser in your race car?
I do hope you are able to prove me wrong, and would love to see the photos and specifics of your project as it progresses.
You might like to persue your marine conversion idea in the appropriate forum on this site, and do some reading there.
Good Luck, Don

 

kapt d everything can be improved thinking out side the box gets you to the top real fast my pro mod shattered the natianal speed record this week by a 10th of a second over the rest of the field they said it couldnt be done but every hour spent on research is money well spent when i said i have not spent a cent i meant i havent spent a cent yet i plan to buy the best of everything no cheap crap that does not work or perform to my standards that are much higher then most peoples. i was planning to use a briggs motor in another project a much smaller boat 14' to 15' foot light weight and i was just passing on some info i would be more then happy to send you pics dyno sheets and referances to the many motors i have built for race boats several of which hold speed records. but this boat isnt about speed its about efficiency and reliability fuel savings and usability. I hold a ba in induction technology and also a ba in aerodynamics i understand metalurgy better then most out there my specialty is building race cars very fast ones and i beleive every thing can be improved made stronger lighter

 

Hi Slo,

I'm quite interested in both your approach and your results. Thinking outside the box is the heart of innovation. I wouldn't worry much about going head to head with the big boys in R & D. It sounds like you have more than enough of a blend of book learning and field experience.

Most marine engines are marinized versions of common industrial engines anyway. A man with a metalurgical backround won't go far wrong.

I'm interested in learning more about the dry film coatings and cryogenic hardening etc.

As for lighter and stronger, LOL, that is certainly true for racing vehicles, cars or boats. I'm old school when it comes to the sea. I prefer stronger and more robust. I know the engineers can prove me wrong but we have always lived by the rule of thumb; if can't bend, it won't break!

Hope to see much more of your project on the marinization site on this forum (which definiteley need a bit more active participation in my most modest opinion.)

 

A 20 to 24 ft boat will have a displacement speed (cheap on fuel) of at best 5K.

IF you are willing to go this slow and the boat full of everything is 4 tons or so ,it will only take 6 to 10 hp to zip along.

A 15 hp takeout diesel, yanmar or kubota , from an old reefer cooling unit will be under $500.

Is this what you have in mind in terms of performance?

FF

 

Slo Troller,
You are dead on when you say "everything can be improved on".
Why don't you start with your punctuation, capital letters, and paragraphs so that your intentions can be clearly understood by the reader?
Ted, far be it from me to discourage "thinking outside the box", however if you are going fishing in rough water, and dont want to end up on the rocks, I would reccomend some conventional wisdom in your choice of engine/drive train, then look for ways to make it better. A calm lake or pond would be a good choice for testing your "outside the box" experiments.
I have had way too many fishing days cut short by tinkerers who thought they had invented a better mousetrap, then needed a tow to get home!
Good luck, Don