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ID: 175 Title: Yanmar Saildrives Please Help!!! Replis: 2 Read: 1910 Author: 3
Name: Mark K.  Posts: 3    Vancouver Time: 2004-7-27_16:36:56 Quote    Reply
I need to replace or rebuild 2 Yanmar 3GM30FC saildrives in a 43 foot sailing catamaran. The old ones are 27 hp with the SD20 saildrive and have about 3000 hours on them and were submerged in salt water for about 3 days. Once removed from the water they were taken apart, washed and oiled. I think I have about 5 options. The first is to have the whole units rebuilt. Does anyone know a good place to get these rebuilt and what the cost is? The second option is to replace just the engine and overhaul the drives myself. Does anyone know where to buy just a new engine and what the cost is? My third option is to replace the whole system with the newer Yanmar 3YM30CE version that is 29 hp. I think that this is a bolt in replacement. My forth option is to replace them with the larger 3JH4CE Yanmar with the SD40 saildrive. This is the 40 hp version and looks like it costs about $1500 more each over the 29 hp units. Has anyone replaced the smaller and older 27 hp unit with the newer 29 or 40 hp unit? I know the mounts are different with the 40 hp. How much added work and how difficult is this? The fifth option is to replace them with other units. Are the Volvo units identical to the Yanmar units? Can you buy them for a better price? Has anyone had any experience with other saildrives? How difficult are they to adapt? What do you think about going to V drives with a conventional shaft and prop? On all of these I have the option of fixed (about $600 each!) or folding props (about $1400 each!!!!!) what is better and why? How much more power cruise speed would you expect to have going from 27 to 29 or 40 hp? Most people claim the boat is underpowered with the 27 hp engines and will do about 7 to 8 knots top. Any general or specific help or advice is appreciated. Thanks in advance. Mark
Name: Phordman  Posts: 1    Vancouver Time: 2004-8-24_11:0:30 Quote    Reply
hello all Im new here. After we got our 41' yorktown lastyear, on our trip from long beach to morro bay we had fule delivery issues, untill I found it was a hole in the tank I was planning a compleat rebuild, as we had already replaced everything. after reading the manuals for the yanmar motors I instantly fell in love with them. they are soo easily rebuildable, just do a search for local yanmar dealers in your area. btw we have the 3ghm (30hp) and it moves our 28,000# boat at 7 knots
Name: Andy  Posts: 3    Vancouver Time: 2004-8-27_20:28:42 Quote    Reply
I will answer your question about the propeller fixed vrs folding. The advantage of useing folding props is that they create much less drag than fixed props due. Imagine pulling a 5 gallon bucket (fixed prop) or a broom stick (folding) along behind your boat. You probably bought the cat expecting better speed and performance than you would get out of a monohull. less drag = better performance. The disadvantage to folding props is that they fold, somtimes when you dont want them to like when backing down, they can get stuck closed on one or both blades (folded) if this happens you have not propulsion at all and perhaps if just one blade sticks incredible vibration with the engine in gear. (this should be obvious and you would imediatly take the engine out of gear) as far as propellers are concerned you have a third option... that would be a feathering prop. such as a max-prop these are much better than folding as it is almost impossible for them to stick closed. They dont fold up when the boat is backing down and in fact give you better reverse thrust than a conventional propeller. Of course you get what you pay for ... the max-prop will most likly cost you 2 to 3 times what a folding propeller will It boils down to what you want and your budget, if perfomance is important get either a folding or feathering prop. For performance and better relability get the max For the ultimate reliability, lower sailing performance and the least cost get a fixed prop. Captain Andy Kurtz