How to grease the prop shaft ?

[Lancerbye]

As Lepke stated. You have a dry stuffing box. My old commercial fishing boat had a 1/8 npt type plug on the top of the housing. That was to fit a grease zerk to add grease to the packing. Since this was located under a cover in a fish hold normally covered with ice, I ran a 1/4 in. tubing up into the wheelhouse permanently attached to a grease gun. Easy to give it a few shots from time to time.

[Clivevon]

As you say you are new to all this: are you sure you have a stuffing box? You might have a more modern type of seal called a dripless shaft seal, like this: https://www.pbo.co.uk/gear/dripless-...rs-guide-17357

A traditional stuffing box works like this: PM&I: Marine Stuffing Boxes: How Does a Marine Stuffing Box Work?
It does need regular greasing, but its not the shaft - its the stuffing box.

You are right to be concerned about disturbing the seal. You do need to know what you are doing before you start mucking around with either kind of seal. You do not want to sink the boat. But just greasing a stuffing box is a very simple routine thing to do & should not cause any problems.

[Marathon1150]

The Volvo dripless shaft seal requires lubrication. One procedure is to use a plastic drinking straw loaded with an inch or so of Volvo shaft grease. After flattening the end of the straw, slip it under the rubber seal and squeeze the grease into the void. Plastic drinking straws are becoming hard to find so it might be best to get several years worth which is not many if using only one per year.

More ideas and a very good illustration (if you have this type of seal) can be found here: https://forums.ybw.com/index.php?thr...t%20all%20done.

[svfinlandia]

IMHO, what you are hearing with the boat out of the water while turning the shaft with everything dry is the Cutlass bearing squeaking. It is normal. Ignore it.
If you want to find out for sure, pour a couple of cups of water into the top of the cutlass bearing while turning the propeller. The Squeak should stop.

S/V Finlandia

[Dougtiff]

Year's ago, while hauled out in Penang, Malaysia to replace a prop shaft on my 36 ft. Yawl, the CUTLESS bearing needed to be replaced, the rubber type normally used on small craft was not available, so the yard turned one out of some kind of really HARD wood, used on ship's, lasted forever, also had a grease fitting on the stuffing box, to stop drip's when not motoring, had a grease gun connected to box, easy to pump a stroke in the unit.

[Richv]

Originally Posted by gamayun

Are you sure about this (the spelling rather than the bearing often being without a cut)? I can find no references to a "cutless bearing" and spell checker doesn't accept the word either. If I recall, the cutlass bearing on my boat had grooves running vertical in the direction of the shaft. Isn't this the norm?

It's properly called a stave bearing.
From Wikipedia:
"The tradename "Cutless" is a registered trademark owned by Duramax Marine. The name refers to a molded rubber bearing manufactured by Duramax Marine.[6] The tradename "Cutless" is used for these rubber bearings and this name has also, along with its misspelling 'Cutlass', become a generic term for them.[7]"

[Bycrick]

I remember somewhere buying one of these bearings during a haulout. The box was prominently labeled CUTLASS BEARING, with a picture of the appropriate sword. Sort of like the local auto parts store called NAZCAR, "It’s the lines." I supposed it helps keep the intellectual property attorneys away.

[bailsout]

Maybe we should call it a shaft bushing. 😁

[Richv]

Originally Posted by bailsout

Maybe we should call it a shaft bushing. 😁

Why not use its correct name, "stave bearing?"

[Andreas W]

In commercial shipping it is called a "stern tube bearing".

[Richv]

Originally Posted by Andreas W

In commercial shipping it is called a "stern tube bearing".

Except that this kind of bearing is not only used on boats. The general name is "stave bearing;" this is the same no matter where it's used. Using names which are application specific is less useful. It's a stave bearing if it's used for a propeller shaft, a stationary pump, or a water turbine generator. So why don't we just agree to call it what it is?

[sanibel sailor]

If you call it a stave bearing, no one will know what you are talking about. If you call it a cutlass/cutless bearing, almost everyone knows what that is on a boat. It is actually useful in this setting.
We already have all agreed, just did not agree to the proper stave bearing terminology.

[Nicholson58]

Originally Posted by parkstone bay

At the risk of being seriously pedantic, the bearing often used on yacht propeller shafts is a "cutless" bearing - not a "cutlass" bearing. Reason: the rubber section is a tube (without a cut - because some types of bearing/glands, or more specifically the packing material, IS cut). It ain't a "cutlass" bearing, (like a sword). End of rant.

Autocorrect. Deal with it.

Thanks anyway.

[pendragon]

My 2 cents.........
A cutlass is an old Oldsmobile
A cutless is a bearing

[Richv]

Originally Posted by pendragon

My 2 cents.........
A cutlass is an old Oldsmobile
A cutless is a bearing

And both are names for a stave bearing.