Any input on installing a 3rd inboard trolling motor-Bruce?

[CaptDana]

Faithful-
I have been kicking this idea around for quite some time-- I use my 2 boats -my 28 bert and a 10 meter trojan express for charter fishing on Lake Michigan. These are gas powered and we have only an average 3-5 mile run out to where we fish on a daily basis. My charters are 5.5-6 hrs in length- about :45min to 1 hr of on-plane running, the rest of the time-- 5 hrs trolling- 2-3 mph. With fuel costs increasing- I have started to look at ways to cut fuel consumption. Example: In my 33' 10-meter trojan with twin 454's- I burn an avg of 23.4 gals per trip based on a 150 trip average for the year. This is coming out to about 2 gals/hr at trolling speed. I am investigating putting a 3rd inboard in that is about 25-30hp with a 2:1 tranny, and a folding propeller. I would prefer to stay with gas for the simplicity, however about the only gas option I can find is an Atomic 4. I have looked at data on small diesels and it seems that I can bring the trolling speed fuel burn down to about .6 gal/hr with a small diesel. This would save 1.4 gals of gas/hr or 7 gals per trip.
Trip Savings of 7 gals of gas x $4.25/gal= $29.75/ trip
Extra cost for diesel fuel used would be $.60/gal vs gas fuel pricing
Additional diesel cost- 5 hours trolling x .6 gal/hr= 3.0 gals x $.60/gal=$1.80
$29.75 fuel savings-$1.80 increased cost for using diesel = $27.95 total savings per trip
$27.95 x 150 trips/season=$4192/ yr 5 years = $20,960 and less wear and tear on the 454's since they would be used for running in and out only.
Big question- is this feasable or am I off my rocker? There is 1 boat within 100 miles of me that has done this. I have done many repowers-glass work- custom fab etc. Looking for Pros Cons- input -contact info THANKSSS!

[Bruce]

Besides the fact when the Iranians decide to close the straits to oil passage and now Canada is talking to China about selling its oil to since Odumbo decided the Canadian pipe line is not safe for American land and the oil prices will hit 300 or more a barrel and we'll all be home sitting in the dark, I'll address your issue.

I have done that very thing on a couple of boats. All of them long range trawler styles for lesser fuel consumption.

It works if you can justify the numbers.

I used Yanmar 3GM diesels as that was the main fuel usage.

Atomic 4 engines I guess are still around and be more prevalent up north especially in fresh water areas, but down here they disappeared in the mid 90's. Yes you can use a folding prop from a sailboat but you'll need to be careful in your calculations for prop size, them folders especially 2 blade are tricky on loading.

Either one of the those boats is gonna be real tight to fit that in the bilge area.

A better idea might be since you can do most or all the work yourself is take one of the boats and yank the gas and install a pair of used Perkins or the such lower hp diesels since distance and speed is not your foe but fuel usage is.

That I believe would be more practical.

I've also seen guys use a 25hp outboard mounted on the transom for trolling to save fuel.

If you can dream it, I've probably seen it on its way to the Bahamas.

[John Swick]

That's what some of the charter guys are doing up this way.
25 hp honda or yammie 4stroke on a transom bracket.
It's a bit of a 'git'r done' solution/look, but it's cheap, and it works.

[In Memory Walter K]

Many years ago there was a boat in the mid-island area owned by my ex-brother-in-law and his partner called the Hound Dog. It had 3 engines back in the days of cheap fuel. Ran offshore on 2, trolled all day on the center one. The boat ended up in Montauk for a while as a charter boat. The one thing you have to figure on in your numbers is the extra maintenance of the engine and it's running gear and controls. They loved it then, but probably wouldn't now.

[AndreF]

During my banking days in Morgan City, when the oil patch dried up in the early 80's, we had to seize some boats. One, I met at some dock in S Louisiana, I think a 110 foot crew boat, with a Captain as after the boat tied up as directed, the whole crew was dismissed (by US Marshalls), much to their suprise and dismay. I felt sorry for them, I knew they would not be paid and they knew it too.
After we were underway, I went down below. The engine room was spotless-took your breath away. The three engines each had an elaborate plackard bolted to it with the name of each engine displayed - "Huey" "Dewey" and "Louie"- I think it was stainless. The Captain was only running "Huey" and "Louie", "Dewey" was shut down. When I got back on the bridge I asked the Captain about sleeping "Dewey" and he said "Dewey" would only add a couple of knots. He lit "Dewey" up to show me and sure enough we only picked up two knots.
Of course, slugging it out running in in heavy seas from offshore with a full load, the third engine would help alot more. Any help climbing those waves is appreciated-less puckering. We were light boat then.

[jackryan]

I ran across this website for electric engines:

http://www.elcomotoryachts.com/elco-ep-motor-7000.shtml

Sounds like a hybrid engine for a boat. Probably not practical for your application, but might work for a new construction single screw boat.

JR

[jspiezio]

MOTOR SPECIFICATIONS
EP-2000 Elco EP-2000
Length 21"
Width 16.22”
Height 18.32”
Weight 260 lbs

The motor is small enough that it could work.


It's the batteries that kill you-

ELECTRICAL SYSTEM
PERFORMANCE
Volts 72 vdc
Amp/hrs 220 amp/hrs
Number of batteries 6
Battery weight (95-135 lbs each - Lithium Wet Cell, AGM, Lithium Iron Phosphate) 518-1,208 lbs (total)
Charger(s) 2x36 volt

[In Memory Walter K]

Which is what's going to be the electric car's (and America's) next problem.

[Bruce]

*Performance is based on battery power only - Run time can be continuous with Genset

Not even close to being practical unless you live on a lake that does not allow for combustion engines.

Anyone who has not been involved with heavy battery powered systems and what the discharge rates are, what the charge rates need to be and the limited number of charge cycles that a bank can handle should do some serious reading on the matter because it will quickly dispel the notion that battery powered stuff has any real potential at this point.

Forgetting all together up keep costs.

Think Chevy Volt.

Battery operated tools are just a small example of what happens on a grander scale with much less control fuss.

If you've got a gen set big enough to handle the chargers to charge the batteries your already running an engine so why do you want to add a bunch of dead weight for absolutely NOTHING!