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Karstein Egeland
08-29-2005, 11:47 pm
Hello! I am thinking of repowering to something smaller than the original md 21 this autumn. Due to the choice of engine size I should like to know what the actual displacement of the boat is. The numbers on different boats I have seen vary a lot, but it may be due to estimates. It seems obvious that it is heavier than the original 5.5000 kg, but how heavy? If someone have weighted their own boat I should very much like to know the result. My Rasmus is nr 588 from 1977 with teak deck. Best Regards Karstein Egeland

Dave DeWolfe
08-30-2005, 02:58 am
I weighed mine - hull #330. No rigging, no mast, no water, no fuel, no batteries. 13,300 lbs.

Eric Richardson
10-05-2005, 11:56 pm
I was told that my boat weighed about 8 tons when in full trim. I am carrying out a refit and have installed a Beta Marine (Kubota) 50hp engine but not yet done any trials. She will not bhe in the water untill may 2006.

e.j.
10-10-2005, 01:12 am
Hi Karstein, Have you already decided on the engine size? I am also considering the same operation... Thanks.

Jan Porshult
10-11-2005, 12:41 am
Hello! I installed new engine year 2000. Volvo Penta 50 hp. It works very well. I run it on 1500-1700 rpm, speed 5,5 knot, 1,3 lit/hour. 3 wings perm screw. Displacement 7200 kg incl water and fuel. Hull no 412.

eric
10-11-2005, 08:19 am
I've decided on the Yanmar 3JH4, 40hp @3000rpm. I will be repowering this winter. I was warned that while the old Volvo was really closer to 50hp than 75, it had an heck of alot of totque. Well, I got out the torque curves for both and the Yanmar has a bit more from 2,000 down while the Volvo is much flatter and torqueier (but not by much)from 2,000 to 3,000rpm. The MD 21 was more power than she ever needed, says I:-), and I feel quite comfortable that the Yanmar will be plenty of power; we'll see. eric, Hull #337.

Karstein Egeland
10-16-2005, 08:06 pm
Thank You for responding to my letter. I have based my choice for engine on an estimate of 7 tons. My choice for engine is the Beta 1005 28 hp, PRM 2,5:1 ratio, and a fixed Campbell Sailor 15X8 prop. According to the calculations this should give hull speed (7 knots) and a good cruising speed at around 6,5 knots at 2700-3000 rpm. The engine is not mounted yet so I have not been able to do sea-trials. The engine is small. However the boat is slim and with a relatively low profile, compared to modern boats. I prefer cruising on higher rpm than would be normal with bigger engine. If someone wants further information on my installation I would be glad to share my experience; send e-mail to ka-egela@online.no.

pim
12-12-2005, 06:06 am
I have now mounted the new engine as mentioned. The prop is however a standard three-blade 15x9. On the trials the boat easily reached hull speed at 7 knots on flat water and no wind at full throttle. It cruised smoothly and quietly at 6.4 knots on 2900 rpm. In 14 knots headwind it cruised at 6 knots on that same rpm. I also mounted a Vetus bullflex flexible coupling. The thrust in reverse is somewhat weaker than with the md 21, however satisfactorly. Karstein Egeland

Martin Hinders
12-22-2005, 01:31 am
Merry Christmas! My boat was reported to have a displacement of 11500 kgs when lifted out of the water at Crete in Greece approx 2 weeks ago. The travel lift is brand new and corrections factors supplied with the lift. My boat is equipped for long distance crusing, MD21A, empty water, 50% diesel volume, all gear in the boat. I am still surprised by the considerable weight. Best regards, Martin