Re: How good is Mercruiser`s V8 DIESEL Engine`s
I am looking at the Mercruiser website now, and I don't see any V8 diesel options. There are, however, three outfits in the USA that marinize the GM 6.5 L V8 diesel. Best is Penninsular Diesel, in Michigan. They get 300 plus HP out of a turbocharged version. Also an outfit in Stillwater, Oklahoma, that puts a belt driven supercharger on that same engine with similar performance but slightly easier installation without the clearance problems characteristic of the rear mounted turbo engines. Also International Diesel Ltd., of Ronkonkoma,(Long Island), NY. They make a turbo charged version of the 6.5L diesel @ around 300 HP. International says they are working on a marinization of the 6.6 L GM Duramax engine, but I haven't seen anything in production yet. I put one of these 6.5L V8 diesels from International in my 1987 Bayliner 28 foot Flying bridge. It was a lot of work, but performance seems good. Right now I am having trouble with the Bravo 3 outdrive, so have not had a chance for any sea trials or fuel consumption tests. The Achilles Heel of these 6.5 L GM diesels is overheating. One serious overheating can put cracks across the valve seats, leading to much lower compression and ultimately to burned valves, and also they tend to crack or warp the center main bearing saddle in the block leading to lower end failure.
Do you have the room for a 6 cylinder Volvo diesel setup in your boat? Probably more reliable, but more expensive than Mercruiser(?) Mercruiser 6 cylinder diesels are based on two engines, one being the Cummins 5.9 L which has a good record in Dodge pickup trucks, and the other is a 4.2 L Cummins based on an Italian block by VM Motori.
