Rudder playing the trumpet

[DITB]

I just changed a 2 foot length of copper, as well as all four flexible hoses, on my rudder (55' sailing cat, HyDrive 150 / 105 hydraulic rudder system).

All went well, as I took the time to study manuals and got plenty advice from HyDrive.

Cylinders are working great, all is as it should be, except ... in starboard side, turning from around 20 degrees right to full deflection, makes this awful "trumpet sound" resonance coming from the rudder stock.

The blue bit in the video is grease - tried that (and probably the wrong grease, should it be rudder stock grease?). I don't see any pressure lube points on the stock itself, only on the HyDrive cylinders.

Several layers of ... nylon or whatever, does this mean the rudders should NOT be greased?

Thank you for helping.

Links to the first video:

https://www.youtube.com/watch?v=yQr8LgtDhlM

Maybe it sounds more like a bagpipe? Imagine if I could play that famous Scottish bagpipe melody "Scotland the Brave", using only my rudders. Just need to practice a little.

In the second video, you can see that when moving the helm faster, the sound stops (towards the end of the video clip):

https://www.youtube.com/watch?v=Im15h4iyc-Q

[JPA Cate]

Ifthere's a nylon bearing under water, they can swell up and make a groaning sound. Cure is to remove the rudder and ream out the bearing for more clearance.

My guess is that something is not straight, something is binding when you make it turn.

Now a proper multihull sailor will be along in a minute or two, and perhaps can help better than me.

ann

[DITB]

Actually, I think the grease must have worked its way into the rudderstock "bearing" itself, as shortly after I took the last video ... the sound went away. Didn't come back again, at least not yet.

We bled the system using auto pilot pump and helm in turn, and eventually I couldn't reproduce the sound at all.

This vessel hasn't sailed much at all the last three years, only a few times per year. Not moving about too much is usually bad for most systems, so it was probably just that.

The final question I have then: Looking at those videos - is it either required, not required or downright damaging, to add grease to this kind of rudder system?

With no grease nipple, one could suspect no greasing is required/desired. I did use the grease gun, up against the surfaces that move, to force the grease as deep in as I could.

Depending on what advice I receive here, I will consider to grease the other rudder as well (which didn't make any particular sounds).

After finishing up the work on the rudders, I am quite pleased with the outcome (considering I didn't mess with rudders before)

[HappyMdRSailor]

Before watching the videos... I was thinking that "trumpet" was the wrong sound.... But I think you nailed it in the below deck vid !

Video at the helm sounds more like somebody stepping on a goose...

Glad this problem worked itself out... New builds (assemblies) can do this... I don't think there's any problem putting grease anywhere you want...

Thanks for sharing

[DITB]

Originally Posted by HappyMdRSailor

Before watching the videos... I was thinking that "trumpet" was the wrong sound.... But I think you nailed it in the below deck vid !

Video at the helm sounds more like somebody stepping on a goose...

Glad this problem worked itself out... New builds (assemblies) can do this... I don't think there's any problem putting grease anywhere you want...

Thanks for sharing

I was unsure whether I would call the sound "trumpet" or "bagpipes", although for bagpipes, there are more tones at the same time. My rudder can only play one tone at a time. Or rather, could, as the sound is gone (for now)

It's definitely not a new build, but as I wrote, it hasn't been used too much (I should remember to operate it more often, even when I am not sailing).

If no other objections, I will grease port side as well. As the Chinese say ... "add oil!"

[HappyMdRSailor]

Originally Posted by DITB

I was unsure whether I would call the sound "trumpet" or "bagpipes", although for bagpipes, there are more tones at the same time. My rudder can only play one tone at a time. Or rather, could, as the sound is gone (for now)

It's definitely not a new build, but as I wrote, it hasn't been used too much (I should remember to operate it more often, even when I am not sailing).

If no other objections, I will grease port side as well. As the Chinese say ... "add oil!"

I see what you're saying... For bagpipes, you would need to raft at least 3 noisy helm boats together and have a "conductor" coordinate...

I misread the refit, and now see it was only plumbing... Not linkage/arms/ram...

Lube away !

[Privilege]

I suspect that the noise was not coming from your steering system but rather from the rudder stock where it goes through the hull. If it hasn't been used, or especially if the boat has just been out of the water, the bearings can get squeaky. If it happens again, the easiest way to isolate the problem is to unbolt the steering arm from the rudder and turn the rudder by hand. If the noise is still there, then its a rudder issue. If the noise fges away its a steering problem.

[deblen]

A few shots of spray Fluid Film on rudder stock just above plastic bearing is good.
It contains lanolin (sheep grease) & withstands washing off by water very well.

It seems the grease that you used eventually worked it's way into squeaky spot & that's great.

Cheers/ Len

[DITB]

My biggest concern was using grease or not.

And as I wrote, the sound went away, and all works perfectly. No need to wait for oncoming problems any time soon, so I'll go ahead and lube it up as recommended.

"Fluid Film" sounds like what I need - I knew for sure WD40 would only have been a very temporary fix so never resorted to that. If that fluid film has a small tube like WD40 and contact cleaner, then it's just what I need.

We actually have lanolin already (for treating cloth diapers, of all things!). Who would guess what a rudder and a babys butt have in common ...

Thank you, forum!

I have a lot of jobs in front of me, so this is not the last you heard of me this year.

[Boatyarddog]

If you use any grease go with silicon grease. A delightful sound that is, especially after 2000 miles.


Sent from SV Cloud Duster

[DITB]

Update on the rudders:

Apart from the DENSO petroleum wax tape, I have concluded the servicing successfully. I wish I would have taken more pictures during the process. I couldn't find sufficient DIY guidance online (had hoped for some instructional videos, but could only find some from other brands of hydraulic steering).

The following points are based on the manual, feedback here, my own recent experience as well as very generous help via email from HyDrive in Australia:

• Loc-Tite mentioned in the manual, recommended by HyDrive is #680 (there are many different variants)
• Straining oil (both new/recycled): Using pantyhose (!) mounted in the funnel -> all oil is filtered simultaneously as bleeding (easy and efficient). Attach the "filter" so it's clear of the funnel intake (to ensure sufficient flow)
• During bleeding, blockage of helm could be due to fully opposed rudders
• Each cylinder has TWO bleeding valves. These are the ones that must NOT be opened more than three turns (not the helm pump, it doesn't have a valve on top, just a "hose-tail plug")
• All oil goes IN to the helm pump and OUT from the cylinders (from bleeding valves)
• As for greasing - "Fluid Film" was suggested in this thread, thank you, it's on my shopping list now
• Finish off with DENSO petroleum tape, ie 75mm #8101003 (10 meter in a roll)

Is filtering really needed?



As pantyhose for woman are readily available worldwide, that was the easiest and cheapest part to find. My only regret is I should have gotten black ones, I really despise that light brown colour. Well, at least the debris shows better - see the picture above, looking into the toe of the stocking!