Info on hull diesel repowers ........

[Phils]

Hi all
i am doing a full refit on an 89 300 weekender, which also includes engines.
Refit is to two berth, no generator.
I am a diesel fitter so am considering going diesel. Ideally would fit the gmc v8 but that is too unreliable, crank cases a bit weak. As such I am looking at several other engines, which is where it comes unglued. A good Diesel engine that will last is somewhat heavy. I would like to know if anyone out there has fit diesels into this hull, ie weekender or da. I will be doing conversion as also have a small engineering workshop, so cost not a critical figure, in that will get commercial engine and marinise myself.
if they have what sort of weight where they. Standard bbc are about 600lbs but lightest reasonable diesel I am thinking about is 1100 lbs, best option was 1600 lbs each!
of course if you have other weight capacity info that would also be usefull.
i am also interested to know the fuel consumption estimates and planing speed estimates etc for the already completed conversions, no point in reinventing the wheel!
anyway any info gratefully received.

 

[fwebster]

Take a look at the 4 cyl Yanmar diesel. A good place to start is Mastry Engine center, who is a Yanmar distributor. Their website has a lot of specs, power, torque, etc info on it. I looked at repowering an older boat about 10 years ago. They recommended the 240hp 4 cyl, but this was a 40 ft boat and I felt the 300 hp 6 cyl was a better fit, that and the cost led me in another direction. The 240 hp 4 cyl is a good light weight high speed engine, but you will need a different ratio heavier transmission......but I think you are going to be under 1000 lbs. I have run a 340 Sedan Sea Ray with these engines and the power was adequate and efficiency off the charts......they just don't burn much fuel. This repower is more than engines and has some hidden costs in it.........larger shafts, new props, add a fuel return system, new gauge package, redesigned battery system, engine rewiring, new engine senders, add primary fuel filters, clean fuel tanks, etc. Also, the 300WE has deep prop pockets which are going to limit the diameter of the props you can use, so you may have to buy different angle struts to lower the prop tips in the tunnel and change the engine beds to accommodate the new shaft angle.

This will be a fun project to watch........take lots of photos and keep posting!

 

[Pietro]

The 300 DA/weekender was a popular boat in the '90 in Italy, and most had 200HP in-line 6 cyl Volvo straights and they have a good reputation, so it wouldn't too difficult to repower with new diesels!