I’m finally getting to sail Summer Song and like it. All the boats I’ver sailed on previously were always left in reverse while sailing and although I forget the argument reverse makes sense to me. Last time out I had the transmission in reverse and noticed a very steady click-click click that sounded like a clock ticking. I shifted the tranny into forward and the noise went away. Today I was out and had the tranny in forward and noticed the same noise. Shifted into reverse and the noise went away. First time out wind was 12 mph +/- a little and today it was not very much to 8 mph or so. Boat is “V” drive with 2 bladed fixed prop.
I am real curious as to what the noise might have been, does anyone have any ideas?
Bill, what prop does your boat have? What engine and what transmission? That information may be helpful in determine the source of the noise.
Mark Powers
Not an answer to your question but the reason for being in reverse is that for most marine gears freewheeling in forward gear will wear out the friction plates and neutral (which is safe too) makes too much noise.
Mark, the engine is a Westerbeke W27 with a V drive. I do not know the make of the propeller but it is a 2 blade fixed propeller and if I were to guess i would guess it is the original one. My situation yesterday was such that it was very inconvenient to open the engine compartment and put my hand on ther driveshaft but next time it happens i will.
Paul, will the prop freewheel when transmission is in forward and boat is moving? The noise I heard I equated to the prop rotating but I wouldn’t have thought that was possible if everything was working they way it should. I read an article a number of years ago that I don’t clearly remember but the author presented arguments for what gear to leave sailboats in when sailing and there were pros and cons to both forward and reverse. What I do remember about the article is that I decided reverse was the gear of choice.
The prop wants to turn in a forward direction as the boat moves forward through the water.
If the gear is in neutral it can and it doesn’t try to turn any drive parts. It will make a noticeable noise and on some gears can cause heat problems. This is not a problem on Hurth gears.
If it is in reverse the prop won’t be able to turn anything in the gear. It will be effectively be locked.
If the gear is in forward it will be able to turn the drive plates a little but not fast enough that you will hear it. However it can’t turn the engine so the plates on the engine side of the clutch will be stationary and the shaft side will be “slipping” on them. This is one of the main things that keeps rebuilders in business.
Reviews I have read say there isn’t much difference in drag between locked in reverse and freewheeling in neutral but freewheeling is a little less. I lock mine in reverse because the slight improvement in speed isn’t worth the irritating noise.
I believe there is a big difference in what happens between a folding prop and a fixed one. Mine is a Gory two blade and I shift it into reverse after shutting down to stop the spinning and then back to neutral. On another 30U with the same engine/trans but a 3 blade streaming prop, to stop the spinning, it needs to be shifted into forward and then neutral.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
I’ve spent a lot of time somewhat succesfully racing sailboats; with a folding prop we would orient the driveshaft so that if it was opened the blades would be horizontal. If not in light air a blade would hang down causing drag and that did make a noticeable difference. In heavier air the prop would probably remain closed but it would take energy to hold the blade up. With a two bladed fix prop I would orient it so the blades were vertical in order to minimize drag. We always locked the shaft in reverse. My opinion is that freewheeling wears everything in the transmission whereas locking it in gear doesn’t stress that much. I do need to read up on my V-drive transmission.
Bill, next time at the boat pull the companionway steps and look at the transmission. There should be a plate on it identifying the make and model. Armed with that you can do a bit of research to determine if free wheeling is okay or not with that transmission. If not leave it in reverse. If it is okay to free wheel you can use neutral or reverse. It is transmission dependant. The answer can be different for different types of transmissions from the same manufacturer.
I will double check the plate on the transmission but according to the owner’s manual that came with my boat I have a Hurst HB 150 which is now known as a ZF 15 M. It took some time but I found this link https://simplicity-marine.com/pdf/ZF/RepairManual%20ZF3M%20Thru%20ZF%2030M.pdf to the ZF 3M to 30M repair manual. Some interesting reading. Is there a better place to post this link to make it easier to find?
This is on page 33. Am I reading it wrong or is there conflicting information on letting the prop spin?
3.5 Sailing or moving in tow
Rotation of the propeller while the boat is sailing, being towed, or anchored in a river, as well as operation of the engine with the propeller stopped (for charging the battery), will have no detrimental effects on the gearbox.
IMPORTANT
When the boat is sailing (engine stopped), the gear lever must be in zero position. Never put the gear lever in the pos-ition corresponding to the direction of travel of the boat.
Locking the propeller shaft by an additional brake is not required: use the gear lever position opposite your direction of travel for this purpose.
I don’t think the section is as clear as it could be but on my read it does not conflict.
The first part says you can let the prop free wheel without harm to the transmission ( leaving it in neutral). The second part says leave it in neutral and never it put the transmission in forward if the boat is moving forward. That last part says you don’t need a separate prop shaft lock if you don’t want the prop shaft to free wheel, you can put the transmission in reverse to lock the transmission when moving forward (sailing or being towed). On the off chance that you try to tow the boat backward leave the transmission in neutral or forward (if going backward with the engine off don’t have the transmission in reverse). It is also possible that you boat is moored where there is strong current. If the boat can’t swing to face the current, leave the transmission in neutral.
I am about to install a Gori two blade folding prop, I don’t see how it could turn and engine when folded. I will be converting to electric drive in a few weeks and I imagine that the electric motor would have very little resistance to a turning prop. There is no neutral with an electric motor, only forward or reverse. Hmmmm . . . I’ll report back on this later.
To the best of my knowledge you can’t spin a diesel engine from the prop turning unless you have a compression release lever which Westerbekes don’t have. However, there are kits out there to harness a spinning shaft to drive a generator.
Joe Valinoti
S/V iL Gatto NS30U #221
Sea Harbour YC
Oriental, NC USA
If you’re about to install an electric motor, you might want to check whether it supports regenerative charging. Many do, e.g., the Electric Yacht QuietTorque 10 that’s been discussed elsewhere in threads about going electric.
With regenerative charging, the freewheeling prop under sail helps recharge the batteries.
Everyone above is correct that a folding prop won’t rotate the shaft, and that it improves performance under sail. With a diesel, that’s win-win.
With an electric, the tradeoffs between folding and fixed prop are different. The folding prop will still improve sailing performance. But because it won’t rotate the shaft, you can’t recharge the batteries under sail with one. While the fixed prop will add charge to your batteries at no extra cost, the folding prop does nothing to help with motoring.
With an e-boat, the tradeoff is paying extra for a folding prop and gaining sailing speed vs. saving the cost of the new prop and gaining motoring range.
