Diesel in a 20 CC

[jw]

Board,
This fall when I start to finish My project 20 cc I/O. I am seiously considering the new Cummins/mercuiser 4 cylinder diesel. Anyone else tried or thought of this. The boat needsa new power plant and from what i heard the Diesel is not that much more than the gas .
Any Thoughts?
Thanks,
JW

[JohnB]

I don't have first hand experiance with diesels in SeaCrafts, but you might want to check the weight. The diesels in almost all applications weigh more than their gas counerparts. In a 23, it might be doable, but I don't think a 20 could take that kind of weight without disrupting the balance in a negative way.

[RAHIM NAHIM]

J.W

I work with Mercury Latin America & Caribbean divison.I export a boat called the panga. it's 27 ft long. powered with a CMD 1.7 Diesel. We are selling them very well. We have fisherman that have logged over 1000 hours on them. To give you a rundown. The 27 ft boat weighs 2500 lbs with engine add 650lbs boat does 35 mph. efficency is incredible. 3 gallons per hour WOT. Now trolling speed you will do less than 1 gallon per hour. Range is over 500 miles. The beauty about this engine is that it does 4500 rpm. We have loaded the boat with seven adults and it doesn't affect speed. Engine will pay off on itself with the price of gas now adays. the 1.7 is gaining a lot of popularity in California with the long range tuna fisherman traveling 200 miles offshore to catch tuna. horsepower is 120 with inline -4 (direct injection)I believe it's the engine of the future.

"Tight Lines"

[Miles Offshore]

JW- my and 2 other former police boats came equiped with deisels. The police didnt like them because they were too loud,( I wish they had left them in). My concern in a 20' boat would be the extra weight. They sit kinda ass heavy with a gas I/O anyway - I dont know what the difference is between gas and deisel is but that is the first thing I would look at. With the extra cost you can probably by 3 gas motors. Also remember you have to add a return line to your fuel tank as well. JMHO-

[Abe's Rocket]

If you go onto the Blackfin web site they discusss, in detail, gas-to-diesel conversions and they discourage it based on how much additional weight it adds and that the boats aren't designed to handle it. Would be cool though...

[Briguy]

Hold on a second fellows. Before you talk a member out of this lets get our facts in line. I am going to assume a mercury 4.3 v6 is the standard replacement for this boat. With a alpha 1, it weighs 865lbs according to Merc's website and puts out 190hp. The gas 4cyl puts out 135 hp and weighs 635 also with an alpha 1. The 1.7 liter diesel puts out 120 hp and weighs 635lbs without the drive. I believe I have seen the diesel package with the alpha for $9995.00 advertised here in fla. You can go to this website and request a price quote. http://www.brownmarine.com/mercdiesel.htm

I remember seeing a shamrock 20' with an inboard 120 yanmar a few years back in boating magazine. It got 30mpg! at idle and about 9mpg at cruise. The range was something rediculous like 1200 miles. Top end just broke 30mph so I would expect a 20' seacraft to do at least that with an io.
Do it! Be the first.

[jw]

I will be checking out prices this summer. I repowered my Charter Rig(1970 36 Hatteras Covertible) Three years ago and have to talk to the man I bought the engines from.
I think I am going to do it. I will have a new fuel tank made with a port for the return line.
As far as speed the 140 in the boat now pushed her fast enough, and it was not proped right, besides my wifes 04 sweet 16 Donzi is damn fast enough!!!
I think the 120 diesel will push the boat great, and burn basically no fuel.
Have fun, I am ready to start fishing.
JW

[ScottM]

JW,
Read the attached boat report of a Trophy 2052 walkaround powered by the 1.7. Pretty impressive numbers - 5.7mpg at criuse (24mph) and 5.4mpg at WOT (32mph)!

http://www.boats.com/content/default...ontentid=16390

[catman115]

Scott, I just read the article.Is that right ? 116 shaft hp?? My 20' seafari had a 135hp on it and was fine. I think the trophy is a wee bit heavier. I do like diesel power..

[ScottM]

Is that right ? 116 shaft hp??

Yup. According to Mercury's web site, the 1.7L is rated at 116 prop hp.