Hallberg Rassy Rasmus 35

Hallberg Rassy Rasmus 35
An Old Classic

Sunday, August 21, 2011

Which engine for the Rasmus?



It needs an engine
 Ok, I am in my fourth year of rebuilding this Rasmus and I am about to order a new ENGINE.  Any thoughts from you Rasmus owners out there on the PERFECT engine for this boat.

6 comments:

Windtraveler said...

Hey Pat, Scott here from Windtraveler. I can't say if it's the perfect engine but we recently (July '10) re-powered with a Yanmar 4JH5E (53 hp). http://www.yanmarmarine.com/theme/yanmar/uploadedFiles/products/engine-files/pleasure-engines/technical-datasheets/pdf/4JH5E.pdf. We got lucky and didn't have to redo the engine mounts. We went with the Hurth/ZF15MA transmission which is an 8 deg down angle trans. We did have one trans issue at about 150 hours and had to send it back for a rebuild (and I've read other similar stories) but we've been fine since and we now have about 800 hours. So I can't exactly push the ZF15MA but the Yanmar has been great!

Pat Sixbey said...

Thanks Scott,

I was originally looking at smaller engines but with the advantage of going with a bigger engine that can drop in without redoing mounts is significant. Did you use the mounts that came with the engine? And you used the same engine mount bolt holes original on the Rasmus? I have kept track of your progress. Very interesting and informative. Tell Brittany us wannabees apprecreciate it. My boat is coming along. Most of the hard grunt work is done. All exterior will be painted by this Fall and I will start screwing and bolting her all back together this winter. I will prolly get the engine sometime this winter. Thanks for the info.

Best Regards

Pat

Lou Linden said...

I installed a Volvo 2003 in 1986 when I bought our boat. Its 3 cylinders drive Barry Duckworth (Hull # 532) at 5.5 kts in more or less flat water. It is not a perfect engine which probably has something to do with why it is no longer manufactured. But the point is that a 28 h.p. engine is more than enough to power the boat as an auxiliary and at .5 gal./hr. it gives a range of about 500 miles. There's plenty of room so maintenance is easier and I used the extra space for a locker for engine spares and a place to stow a 2 HP outboard on long passages (we sailed the boat 30,000 miles in 5 years). It did require adapter plates for the engine mounts. If I had it to do over again I would pick a similar size and power Japanese (Mitsubishi, Yanmar, etc.) engine-trany package.

Juan José said...

The standard power for a sailboat is about 4 HP each 1000 kg displacement

So for a 6500 heavy loaded Rasmus i guess that the best engine you can buy for your boat is the Yanmar 3YM30 (29HP)
(Weight with gear/drive Kg 133)

Regards
JJ

Cabatach said...

|I've been thinking about it and doing the sums as my MD21A won't last forever, though it is trying hard,

The guy in our yard does a good deal on Beta engines, we had a good look and reckoned 35Hp was more than enough. Also giving thought to a folding prop when I do the job. Have any of you got one and is it worth it

Euan from Cabatach

Pat Sixbey said...

I did the calculations based on Dave Gerr's formulas in The Propeller Handbook. It came out to a minimum of 32 hp. If you attach a high power altinator (100 amps) you need to add a 3 or 4 more HP. Also add a couple of HP for mech. loss through the transmission. So depending on what altinator one has, a 30 to 40 hp engine range would work. Right now I am going with a 38 Hp Beta Marine. With a 2.47:1 reduction transmission on this engine, you need a propeller with a 13.58 pitch and a diameter of 17.31 using a 3 blade propeller with a blade area of 132.16 inches squared. The formulas used are from Gerr's book but I did the calculations so I can't swear by the accuracy but I think they are right. :-)