Rudder bearings - what to lubricate with?

[cmedsailor]

Goodmorning and happy new year to all.
I have dropped my rudder for maintenance and since both top bearing (made from “ertacetal” according to Beneteau) and bottom bearing (bronze) seem OK my intention is to clean everything (fiberglass rudder shaft, bronze and nylon bearings and rudder shaft s/s collar), lubricate them and then assembly back.
My question is what to use to lubricate everything before assembling? Normal marine grease? White lithium grease? Graphite grease? Something else?
Bear in mind that:
The lower part that is usually in the water consists of a s/s collar “rotating” around a bronze bearing
The upper part that is usually dry consists of a fiberglass shaft “rotating” around a nylon (ertacetal) bearing
This is NOT an automatic bearing adjustment rudder (neither are any roller bearings)
Thanks

 

[cmedsailor]

Am i the only one who has ever dropped a rudder?

 

[nigelmercier]

Am i the only one who has ever dropped a rudder?

Probably not.

 

[misterg]

I would hazard a guess that the top bearing is self lubricating (some grades of ertacetal have PTFE in the mix) and that (in the presumed absence of greasing points) the bottom bearing is water lubricated.

Clean 'em up and put 'em back?

No doubt a dispute will now rage...

 

[Rossynant]

Ertacetal is low friction itself and used in bearings without lubrication. Can be water lubricated. For bronze (can be also 'self lubricating' kind alloy) water is enough for lubrication. That is theoretical because I have no idea what exactly you have there...
Guess there is no provision for greasing, or instructions to grease - in such case better not use grease for assembly (especially the sticky kind), but light oil (machine oil), can be used almost always.
Forgive me if I messed something in english terminology

 

[oldsaltoz]

I would be tempted to add just washing up liquid to the lower assembly and nothing save a drop of soapy water at the top end just to help it slide into place.

No telling if some oil types may react with the bearing material.

Good luck and fair winds.

 

[dratsea]

Seawater and the bluer the better!

 

[grafozz]

grease nipple ?

I am looking for a grease nipple that can be screwed into the grp rudder tube so I can pump grease into it so lubricating the rudder shaft .
Anyone seen a suitable grease nipple ?

 

[Neil_Y]

Polyacetal's are happy dry, the lower bronze ss set up without a seal or greasing point will be just sea water.

It is usually best to check with the manufacturer as you have, as some materials will prefer dry or water to oil or grease.

Maritex comes in different grades for dry, water, oil/grease in different colours.

 

[Robert Wilson]

Am i the only one who has ever dropped a rudder?

No, you're not - but I thinking about it.
View attachment 23071

For the life of me I can't see how to remove it. The bottom of the rudder terminates in the skeg with no visible signs of removal. The stock, where it exits the hull into the cockpit, is held in place by a double (large) nut assembly. The whole stock is encapsulated through the lazerette.

Presumably if the two nuts are removed then the stock will draw up through/away from the rudder - which will then fall-out of the skeg?

Assuming it can be removed, I can think about which lubricant is suitable!

 

[AndrewB]

My rudder is dropped annually. I avoided greasing the lower bearing (metal to metal) before reassembly when I discovered this trapped dirt in the bearing which caused both friction and wear. The upper bearing (nitrile bearing) needs a stuffing box since it enters the aft cabin at water-level, so has to be greased with a medium waterproof grease.

 

[reeac]

I am looking for a grease nipple that can be screwed into the grp rudder tube so I can pump grease into it so lubricating the rudder shaft .
Anyone seen a suitable grease nipple ?

If all local sources fail then Namrick of Hove [Google them] supply in a range of sizes for restorers of old cars. As far as I can recall they're brass so fairly OK for marine conditions - especially if all greasey.

 

[Tranona]

I am looking for a grease nipple that can be screwed into the grp rudder tube so I can pump grease into it so lubricating the rudder shaft .
Anyone seen a suitable grease nipple ?

Can't see any reason to pump grease into a GRP tube. The bearings are almost certainly water lubricated or have their own grease points.

 

[Tranona]

No, you're not - but I thinking about it.
View attachment 23071

For the life of me I can't see how to remove it. The bottom of the rudder terminates in the skeg with no visible signs of removal. The stock, where it exits the hull into the cockpit, is held in place by a double (large) nut assembly. The whole stock is encapsulated through the lazerette.

Presumably if the two nuts are removed then the stock will draw up through/away from the rudder - which will then fall-out of the skeg?

Assuming it can be removed, I can think about which lubricant is suitable!

Almost certainly there will be a removable shoe at the bottom of the skeg. Scrape off the AF to expose the fastenings.

 

[cmedsailor]

Thank you for all the answers. I have also managed to receive an answer from Beneteau. They recommend graphite grease for the top bushing only.

 

[cmedsailor]

No, you're not - but I thinking about it.
View attachment 23071

For the life of me I can't see how to remove it. The bottom of the rudder terminates in the skeg with no visible signs of removal. The stock, where it exits the hull into the cockpit, is held in place by a double (large) nut assembly. The whole stock is encapsulated through the lazerette.

Presumably if the two nuts are removed then the stock will draw up through/away from the rudder - which will then fall-out of the skeg?

Assuming it can be removed, I can think about which lubricant is suitable!

Be brave! I was postponing mine for ages because it was never urgent. And the main reason I did it now it's because I wanted to remove the shaft and check what causes vibration to my boat.
I spent hours into a lazarette bent into 5 (!), not very confortable for a tall guy (1.88m), and also working through a small hole behind a rear cabin (could fit just my head and one shoulder) to undo everything (including the whole installation of the below deck auto pilot) and drop the rudder. It will be...interesting when I try to assembly everything back.

PS: Nevertheless it was (till now) a very, very satisfying job

 

[oldsaltoz]

My rudder is dropped annually. I avoided greasing the lower bearing (metal to metal) before reassembly when I discovered this trapped dirt in the bearing which caused both friction and wear. The upper bearing (nitrile bearing) needs a stuffing box since it enters the aft cabin at water-level, so has to be greased with a medium waterproof grease.

Ever considered dropping a bit of PVC pipe over the top end and adding a bit of Sikaflex?

Good kuck and fair winds.

 

[Skylark]

PS: Nevertheless it was (till now) a very, very satisfying job

Happy New Year!

That being the case, feel free to drop by Holyhead anytime till Easter where you'll find another one keep you satisfied

 

[cmedsailor]

Happy New Year!

That being the case, feel free to drop by Holyhead anytime till Easter where you'll find another one keep you satisfied

Happy New Year.

It's 4 bolts to loosen the cables and another 4 to remove the quadrant (you have to remove it because there's a 'hidden' pin in there) if you don't have a below deck autopilot.
If you have an extra person to help the whole job can be done easier.

Why do you want to drop it anyway?

 

[AndrewB]

Ever considered dropping a bit of PVC pipe over the top end [of the rudder post] and adding a bit of Sikaflex?

Thanks for the idea, but the pipe would have to be open at the top end to allow the quadrant to rotate. To get the open end well above water level would would mean lengthening the rudder post up through my bunk and suspending the quadrant in the middle of the cabin!