Hi Phillip
Could you please tell me what type and size of motor you have in your 361 as I am considering updating my prop to a 3 blade folding. I have a Volvo Penta 33 HP. 3 cylinder
Folding Props
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Hi Phillip
Could you please tell me what type and size of motor you have in your 361 as I am considering updating my prop to a 3 blade folding. I have a Volvo Penta 33 HP. 3 cylinder
I have a Volvo Penta MD2030D 29hp (2001 built). Are you sure you don't have the same engine? I have never heart of a 33hp VP engine.
I had the same query when I purchased the yacht, the owner and the broker assured me that this was the case.
I have a 2001 361 purchased new with 3 blade prop Yanmar 27 HP no vibration at low or high RPM.
Also get approx .65 gal/hr but at 3,200 RPM approx 6.5 kns/hr.
Found Raymarine wheel pilot would not handle boat in choppy seas installing SX10 Corepack was called 6,001 below deck auto pilot.
Any comments on below deck pilot installation performance?
The rubber round plugs on back of boat over wash hoses have worn out (2nd time).
Any ideas on better solution?
Also get approx .65 gal/hr but at 3,200 RPM approx 6.5 kns/hr.
Found Raymarine wheel pilot would not handle boat in choppy seas installing SX10 Corepack was called 6,001 below deck auto pilot.
Any comments on below deck pilot installation performance?
The rubber round plugs on back of boat over wash hoses have worn out (2nd time).
Any ideas on better solution?
6.5knots @ 3.200rpm is very low. Check the obvious first. If your propeller or hull is dirty (especially the propeller) then definately you will not be able to achieve a high speed. Let me just say that I was achieving around 6,2knots @ 2400rpm, didn't move the boat for around 1 month for some reasons and then suddenly I was only able to achieve around 5.7knots for the same rpm. I cleaned the propeller with a wet paper (not sure if it's called like this), which I must say didn't really look so dirty, and was suddenly back to 6.2knots. I COULDN'T BELIEVE IT. This propeller, honestly, didn't look so dirty (I mean if I didn't bother to check the speed and made this comparison at 2400rpm I would never clean it) but it made a huge difference.
If hull/propeller are clean and you still achieve this low speed at 3200rpm then check the propeller size. What size is it anyway? I would expect it to be something like 16X10 (for a "normal" wide plate fixed propeller).
Regarding the autopilot....
I bought my boat almost 4 years ago and covered around 3500nm so far. I used to have the black raython autohelm unit which was just OK for calm to moderate conditions if going upwind (either sailing or motoring) and could handle only up to almost calm conditions in following seas. Plus I had the problem of the clutch disengaging quite often and in general, despite settings and sail balance, the autopilot was driving the boat +/- some degrees to destination because I could see that the little computer was not so fast to correct.
I replaced the wheel pilot about 2 months ago with a below deck type1 linear drive and the SX10 corepack and I had the opportunity to check it during 2 small passages (50 miles each) and of course lot's of sailing during some weekends and afternoons. SIMPLY AMAZING. You simply cannot compare the two. I was sailing on a broad reach/run for a couple of hours in 20+knots of wind in 2 meters of following seas (where you get this nasty movement from waves lifting the stern) and the autopilot was perfect. Very fast, very stable and could handle the conditions perfectly.
Yes, I paid more than twice the price of a wheelpilot SPX5 but you get what you pay for.
I don't necessarily disagree with the idea of having to run the diesel at 3600, but how necessary is it Really? If you are getting to hull speed at significantly less than 3600, the extra rpm and fuel is wasted anyway. If it is so necessary, why is there a detent in the throttle that kicks is back to about 2500 as soon as one lets go of the throttle lever?
Is the diesel really going to recognize a 400 rpm difference and is it worth a two inch pitch change to regain that difference ?
One cannot run at 3600 in no wake zones either....
You don't run a gas engine in a car all day long at max rpm, why would you do that with a puny little two cylinder diesel in a boat that goes nowhere fast anyway.
Is the diesel really going to recognize a 400 rpm difference and is it worth a two inch pitch change to regain that difference ?
One cannot run at 3600 in no wake zones either....
You don't run a gas engine in a car all day long at max rpm, why would you do that with a puny little two cylinder diesel in a boat that goes nowhere fast anyway.
3600 would usually be the max rated RPM that you should be able to attain in flat water with a clean bottom and prop. You would then want to run the engine somewhere between 70% and 80% of wide open throttle. Yanmar even recommends as much as 10-20 minutes per hour at WOT after prolonged low load operation to keep the engine clean and running strong. These engines prefer to be loaded in this type of application and to have the prop well sized..
Because it is like driving your car up a steep hill in fifth gear all day long instead of finding the right gear for the grade. The max RPM suggestion, made by most all small marine diesel engine companies, is done with good reasoning.
If your prop is over pitched you are essentially over-loading your engine at all engine speeds throughout the RPM range. By doing this you cause your engine to lug and work harder at lower torque and HP than it was specified & designed for. When you add a high output alternator or decent alternator load this gets even worse.
Over propping leads to such things as more frequent exhaust elbow plugging's, soot and carbon and sometimes the cooling systems can have a tough time keeping up because the RW pump GPH is RPM based. Higher RPM equals more water flow. When you give your engien the same "load", at a considerably lower RPM, the RW cooling system may not be able to keep up.
Many manufacturers, including Westerbeke and Universal, will specifically void the warranty if your not within the specified RPM range when at WOT. Most want to see it within +/- 100 RPM
On our boat, with a 44HP Westerbeke, we were over pitched when Norm at West By North sent us an improperly pitched Campbell Sailor. It was off less than 300 RPM yet in the month we used it, while waiting for the correct prop, the soot on the transom was horrible, the worst we've ever experienced, and it is usually very, very light, if any. It did not matter how slow I went, even at below hull speed, the engine was working harder than it should have at that RPM/HP/torque curve, especially when you added in the alternator loads. With the new prop all the sooting is gone...
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