RE-POWER

Bompapen · Post by **Bompapen** » Sun May 15, 2005 8:57 am

Hello I want to repower my 1985 33 Convertible with diesel. My old engines are 454 Merc Rigth and Left rotation. I heard about the GM 6.5L Optimizer Diesel engines. I am interested in these engines because they are a low cost direct replace of big blocks using the same lay out (trans, mounts,wiring,etc) in repower. Any one have an experience with this or simmilar engines? Thanks David Vila

franklyprice · Post by **franklyprice** » Sun May 15, 2005 12:05 pm

David, I've been curious about those engines and read what the manufacturer says about them but haven't seriously considered them, mostly because I'm a long way from any repower. How much does a pair of those go for? I also can't remember them stating any specific horsepower rating. Do you have any horsepower or price #'s yet? Frank Price

Post by **dougl33** » Mon May 16, 2005 9:52 am

David, Welcome aboard. It seems as though most of the re-power discussions on this forum have revolved around 8.1 gas (both Merc and Crusader) and Cat, Cummins, and Yanmar on the diesel side of the argument. Have you tried getting feed back on the GM's at boatdiesel.com? Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth Marblehead, MA

Bompapen · Post by **Bompapen** » Wed May 18, 2005 1:02 pm

FRANK Some sellers like Peninsular,Marine Power and Diesel USA. Specify that this engines Optimizer are not the regular GM 6.5L. This are the engine from the original military Hummer. The HP are 170 natural $12,000, 270 turbo $16,000, 310 turbo aftercooler $17,500 (peninsular and Marine Power)and Diesel USA have a supercharger versions at 300 for $22,000 . Thanks for your time.. David

Post by **dougl33** » Wed May 18, 2005 6:00 pm

At $17.5K for 310hp I think I'd spring for a proven setup like Yanmar or Cummins for approx the same price and hp. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth Marblehead, MA

franklyprice · Post by **franklyprice** » Wed May 18, 2005 6:37 pm

David, The price isn't bad but there are two important things I'd have to consider if I were going to repower with these engines. One, How long will they last? as long as a cummins or yanmar? The other thing I have to ask is, if you repower with these things, would everyone look down their noses at you and think "silly fool, why didn' he just put in yanmars"? And so maybe the resale would suffer? I assume if the resale was less, the amount would be much more than the difference in price between the types of engines, ie; OK now you have diesels, too bad nobody wants your boat because it has hummer engines in it. Sort of an ocean going "red headed step-child" Just a few thoughts. Frank Price

billb · Post by **billb** » Thu May 19, 2005 6:56 am

David: are those prices with gears??if they are thats fair price....last year I bought 2 330b cummins for $17,500 each..without gears...If it were me, I would go with Yanmar,Cummins, or Cats....but those might be very good motors, just try to find someone that has them in their boat.... Bill Beeson 33 bertram RAZZMATAZZ

Bompapen · Post by **Bompapen** » Fri May 20, 2005 7:10 am

This prices are without gears but they are drop ins to the gas trans. No need modifications using same connectors, mounts , shafts etc. I think of this engines because I first considere a same gas replacement. The gas engines are car engines first then modify to marine. My engines are Mark 4 2 bolts main and cast iron crank and last 20 years and over 1000 hrs. This diesels have 4 bolt and nodular crank with large cid vs HP as say in Boatdiesel.com. If I repower with this diesels my cost only increase from the diff on the price of the engine. But if this engines gona give me a head pain I should considere a rebuilt cummins , cat etc. ANY SUGESTION. Bill what is your cruissing Kt with the cummins 330? Thanks to everyone for the help David Vila

Post by **dougl33** » Fri May 20, 2005 7:17 am

Skip the 6.5's and go Cummins, Cats, or Yanmars. Gold Coast Power has got rebuilt 260hp 3208's (without gears) for $11.5K. Regards, Doug L. 1986 33 Bertram FBC Queen Elizabeth Marblehead, MA

jav · Post by **jav** » Fri May 20, 2005 9:46 am

Dave, having done a gas to diesel conversion, I have to agree with the others. Dollar for dollar, I would go with the better known brand names. There would have to be a "substantial" savings to make me consider these. Also, I'm not very familiar with these particular engines but I talked to quite a few folks before attempting my own conversion. The term "Drop in replacement" can be a very misleading. Questions always arise such as: Are these engines available reverse rotation? Can your existing gears be used if not (rotation and torque requirements)? Is the torque curve close enough to your gas engines where the ratio, prop and shafts are marginal? Does your water intake and exhuast system have the capacity to run the diesels? Do you have galvinized gas tank/tanks that have to be switched out? You'll likely need a new fuel filtration system. Are your guages compatible with the diesel outputs (tach especially)? Are your couplers and mounts good enough to deal with a deisels vibration? ... the list goes on. In the end, my engines were only part of my swap over costs... its the little stuff that nickel and dimes you to death. You will through this wether you go with these or a set of Cummins but I tend to beleive the effort will be easier to justify in the latter case.

billb · Post by **billb** » Fri May 20, 2005 11:49 am

David: the 330's Cummins were for my 31 that i used to have..great boat just WET, and not enough creature comforts....the 31 would run 29 knots cruise....and 34 WOT...the 33 I have has 3208's, 270hp which is fine, would like a little more power,but maybe next year.....I know of a 33 sportfish w/330 and it cuises at 25 knots, wot is 30..... also cummins has 6 year major component warranty if you dont charter....which I think is great........ Bill Beeson 33 bertram RAZZMATAZZ