2 questions

Hi all,

surprised hearing of the Volvo recommendation not to take reverse gear position while sailing. I did it alsways on all my boats und since 4 seasons on my 371 (Saildrive/ 2 bladed fixed propellor) too.

I never regarded any problems. The gearbox is working without moaning und the propellor shaft seems strong enough for that.

Is there any competent expert who knows an answer? Isn't it better for the Saildrive to stand thousands of wild and useless rotations or to resist the sometimes hard pressure of water?

Should I at the end being forced changing- o God-  my so beloved attitude? 

Second thing: If it was the batten falling down, so I lost some in strong winds from the jib. So I brought it to the sailmaker and he solved the problem with a few stitches. If it was something of metal: Don't hesitate to climb the mast!

So long and best regards from

Dietmar/ Elisabel 

Hi Franko,

Like I said in my last message. 33% more power for the 3 blade foldingprop according to a 2 blade foldingprop. And not the engine has 33% more power. It stands in the books from volvo. 100:3(blades) =33,3% so because the fact you have 1 blade more and the blades are a little bit larger you become 33% more power in the prop. And this you would imediately notice when you will take a boat with a 2 blade foldingprop and after that the same boat with a 3 bladefoldingprop. A hughe difference!! So much easier to stear in harbours etc. and when you have 25 or 30 knots windspeed right from the front and when you are going on your engine, so much more power(+33,3%)

greetings,

Martijn "NO FEAR" 

Franko,

the Gori folding props are expensive but they should be very good. They do have the advantage with the second speed. Whilst driving forward you can switch in the backwards gear. Then forward again and the engine speed reduces without loosing speed. Thats good for the engine and good for the diesel consumption.

Have a look @ http://www.gori-propeller.dk/Index.asp?IDS=1198

Interesting Site is also to find here:

http://www.flexofold.dk/folding_prop_test_results.htm

Find a copy and paste from FAQ at the flex-o-Fold site:

Q. Should I choose a 2-blade or 3-blade?
A. That depends on what is important to you. A 2-blade is more efficient than a 3-blade (that surprises most people). Thus, a properly sized 2-blade will give you a higher speed at a given RPM in flat water than a properly sized 3-blade. The 2-blade is also lower in drag and less expensive. The 3-blade, because of its larger blade area, will accelerate the boat faster. This means a 3-blade is better around the docks, when powering against a head sea and when stopping. The 3-blade is also smoother if there is anything out of balance in the drive train.

I'm surprised.

Kind regards

Ralf

Hi,

I own 371 hull 212 and i bought it wiht a 3 balade flex-o-fold folding prop.  When I got the quote for the 3-blade prop, they stated it to be a 17*12-3L or 17*13-3L.  I also got a quotation directly from the Flex-o-fold dealer at the same price(but in that case I would have the fixed one as spare). However, I decided to by directly from Hanse to be sure to get the right size!

During my first summer I have been a little bit dissapointed since I need a very high RPM to reach a good speed. At 3000 rpm I reach 6,5 knot at flat water and if I give it full trottel (for a short time) I almost reach 7,5 knots which is good, but the RPM then reach more then 3800. The 3YM30 is rated 29 Hp @3200-3600 rpm. Even if I run the engine at full speed against heavy wind and sea I reach 3800 rpm. My conclution is that it's the speed controller that goes into limit, and not the engine power.

A check of the prop when I lifted my boat (I bought it in Greifswald already i the sea) showed a prop of size 16*10-3L, a big difference from the quoted size. A check with the Flex-o-fold designer showed a interesting history. Flex-o-fold first recomend the larger size but Yanmar did´t approve that. Instead Hanse chosed to deliver boats running with undersized props (this is true not only for the 371). My personal conclution is that Hanse sizes the prop for Charter skippers who don't understand how to run an engine. Full trottle will not destroy the engine but your ears. With this approach you can't either utilize the engine or the Prop.

A proper sized prop should allow the engine to run at it's maximum power and rated RPM at full trottle (for 3YM30 3200-3600 rpm) and then the skipper should reduce the RPM at cruising with 4-500 rpm. Then you get quiter and more economical installation.

So, my recomendation to everyone: Don't by the folding prop directly from Hanse (unless the can promize you a proper sized one), keep the fixed one and by a 2 or 3 blade directly from Flex-o-fold. The price will be the same but you will get the right prop.

I will trye to get Hanse replacing my prop, but I they don't do that I have to by new blades.

/Jesper