New transmission noise while sailing in neutral

[Dave G.]

Officially off OP subject....

 

[Kenneth K]

From the Ericson manual:

 

[supersailor]

Check your owner's manual about freewheeling the prop while sailing. Mine recommends strongly against it because of potential transmission damage.

 

[Christian Williams]

"To reduce drag for more efficient sailing"?

Leave it to Maine Sail to rig up a test....

Fixed vs. Free Wheeling Prop - Test Data

www.sailnet.com

 

[Alan Gomes]

From the Ericson manual:

View attachment 43518

One needs to follow the procedure that is appropriate for the particular transmission, which varies. For example, Yanmar sent out a service advisory stating that the transmission (presumably a Kanzaki box) must be left in neutral while sailing on pain of voiding their warranty. They warn that "internal damage to the gear" may otherwise result. They also suggest, "If the customer desires that the propeller shaft not spin while sailing, either a folding propeller, shaft break, or other suitable device may be used."

On my Yanmar, which has a Kanzaki KM2-A transmission, I always leave it in neutral, per the transmission documentation. Some Yanmars were fitted with Hurth boxes, so in that case I'd go with whatever is appropriate for the Hurth. (If I recall, they allow both reverse as well as neutral, but I'm not sure.)

The bottom line is that it is entirely transmission specific.

 

[Alan Gomes]

Check your owner's manual about freewheeling the prop while sailing. Mine recommends strongly against it because of potential transmission damage.

Is that the owner's manual that came from the engine manufacturer or the owner's manual from Ericson? Ericson's advice is of no value here, at best.

 

[Alan Gomes]

One needs to follow the procedure that is appropriate for the particular transmission, which varies. For example, Yanmar sent out a service advisory stating that the transmission (presumably a Kanzaki box) must be left in neutral while sailing on pain of voiding their warranty. They warn that "internal damage to the gear" may otherwise result. They also suggest, "If the customer desires that the propeller shaft not spin while sailing, either a folding propeller, shaft break, or other suitable device may be used."

On my Yanmar, which has a Kanzaki KM2-A transmission, I always leave it in neutral, per the transmission documentation. Some Yanmars were fitted with Hurth boxes, so in that case I'd go with whatever is appropriate for the Hurth. (If I recall, they allow both reverse as well as neutral, but I'm not sure.)

The bottom line is that it is entirely transmission specific.

Here's the advisory from Yanmar. Again, they are referring to engines fitted with their Kanzaki transmissions specifically.

 

[Kenneth K]

The Ericson manual describes the operation of the transmission that came with the boat. Obviously, if an owner subsequently changes the transmission, he would be well advised to follow the new manufacturer's guidance, and not that of the original manufacturer.

 

[Alan Gomes]

The manual describes the operation of the transmission that came with the boat. Obviously, if an owner subsequently changes the transmission, he would be well advised to follow the new manufacturer's guidance, and not that of the original manufacturer.

Even if the engine that came with the boat is original, I would not trust Ericson's advice over that of the manufacturer. I think it would be prudent to look it up, since the info is usually readily available.

There are tons of posts on this question on different internet fora, such as SBO, by the way. It comes up nearly as often as the "What is the best anchor?" question. Those perennial threads all run along the same lines: Someone posts the question; a bunch of people jump in with what makes sense to them, giving answers all over the map; someone finally posts something direct from the engine/transmission manufacturer that (sometimes, mercifully) quashes the debate.

Transmissions are not cheap to replace. It's worth a few minutes of searching to confirm the proper operation.

 

[Alan Gomes]

According to info in the manual reverse or neutral is fine with a Hurth tranny. Under sail I doubt the prop spins more than a 100 rpm unless surfing downwind and then maybe 200 rpm so not much wear in any case. I sail in neutral but if you put it in gear it should indeed be in reverse per Hurth manual.

I somehow missed your post with info direct from Hurth before I posted mine. So it is indeed neutral or reverse--for a Hurth transmission. But neutral only for the Kanzaki on a Yanmar.

There you have it.

 

[Navman]

I take off my shoe and use my big toe to hold in the glow plug. After 10 seconds or so, I then bend down and hit the starter with my finger. Saves all that awkward positioning. It's a different story in the winter when wearing boots.

 

[Bolo]

The Ericson manual describes the operation of the transmission that came with the boat. Obviously, if an owner subsequently changes the transmission, he would be well advised to follow the new manufacturer's guidance, and not that of the original manufacturer.

This thread got me to thinking about the transmission in my E32-3 because the original Hurth HWB 50 (Which MIGHT be the one the Ericson manual refers to when giving advice as to when to put the shift lever) was replaced with a Twindisc 40P (also referred to as the MG 340 after Twindisc bought Technodrive years ago). You can search for posts about my replacement story on this site.

So what I found in the manual for the Twindisc 40P was this: "NOTE: While sailing with engine off (under sails), the propeller rotation can be inhibited by shifting the transmission in reverse. Under towing, the transmission can be shifted in neutral. When anchoring in water current,
the propeller rotation can be inhibited by shifting the transmission in reverse (rotation opposite to water flow)."

So according to this and Joe DeMers of Sound Marine Diesel, where I purchased the Twindisc 40P (MG 340), and who emailed me and wrote, "Regarding the TMC 40 manual, your question is not directly answered. I interpret the manual as saying you can either lock it in astern while sailing, or let it freewheel.", no harm should come to my transmission if it's left in neutral when under sail. Although it does not say anything about leaving the transmission in forward which is something I don't do and I think most sailors don't either because you normally shift to neutral before shutting the engine down. So like Kenneth K wrote here, it's best to get advice from the manufacturer and distributor of your transmission to know what to do.