Propeller nut sealant

[Jokani]

When I removed the propeller nut, it looks as though it has previously had gasket sealant of some type of adhesive to secure it:

Is this normal practice, and should I seal/glue it again when I replace it?

 

[LadyInBed]

I take it that the prop shaft has not got a hole in to put a pin through.
the other method is a keyed washer that locks in position on the shaft and then is bent over a flat on the nut when it has been tightened up.

 

[Jokani]

I take it that the prop shaft has not got a hole in to put a pin through.

It does have a hole, and there was a spit pin before I removed it. Sorry, I guess it would have been helpful if I had posted that info before.

 

[vyv_cox]

Not normal practice that I am aware of. It could also be Loctite although not used in the right way. No reason to use anything.

 

[pampas]

Its done to stop leakage on the flange face, but most forget to seal the other end. IMHO tis a bit of flannel and really serves no purpose, so don't worry about it.

 

[NickRobinson]

I refitted my prop, castle nut and ss split pin. Before launch I had some epoxy left from installing the cutless so smeared it over the nut, pin and shaft threads on the basis that it was extra and could not any harm

 

[vyv_cox]

Its done to stop leakage on the flange face, but most forget to seal the other end. IMHO tis a bit of flannel and really serves no purpose, so don't worry about it.

??? Leakage to where? There is nothing there that will be affected by water penetration.

 

[pampas]

I know there is nothing to be affected by water penetration but some of these "pro" marine engineers do this sot of thing, in fact I recently was asked to remove a nut that was tight and found that 601 retainer had been applied, asked who did the last refit "Oh so &so" and produced the bill.

On it stated "I thought the threads are worn and firmed up with a special sealed" item cost £2.50

 

[vyv_cox]

It looked to me that the blue stuff in the OP photo is not on the threads, just the mating faces. I'm surprised it is there if the nut was tight, I would have expected it to extrude out.

 

[Jokani]

It looked to me that the blue stuff in the OP photo is not on the threads, just the mating faces. I'm surprised it is there if the nut was tight, I would have expected it to extrude out.

It was definitely tight, it needed a v large spanner to remove, but I guess there must have still been some space between the two.

 

[wrr]

This may have been some gasket material to allow the hole in the prop shaft to align with the hole/castellation in the nut for the cotter (split) pin when it was torqued up.

 

[Jokani]

This may have been some gasket material to allow the hole in the prop shaft to align with the hole/castellation in the nut for the cotter (split) pin when it was torqued up.

That's a good point I was forgetting that I would need to align that hole again!

 

[pampas]

don't flog the nut up tight, firmly at first, keep tightening until a slit pin will enter, job done,

 

[vyv_cox]

don't flog the nut up tight, firmly at first, keep tightening until a slit pin will enter, job done,

Main thing is to ensure that the nut is tight enough. If the gasket material was there to make up a gap it suggests that the nut was not tight enough before, my earlier point. I have recently had to replace the prop on my motorsailer because the nut was not tight enough, allowing the prop to move on the shaft. This resulted in a crack the full length of the boss, fortunately found before the whole prop fell off. This was immediately following a 150 mile voyage, so we were lucky!

 

[Poignard]

A few years ago, I had a new propshaft made by T.Norris Ltd and it came without a hole for a split pin and with an ordinary nut. I was assured that modern locking compounds made split pins and castellated nuts uneccessary.

I wasn't convinced. What works when assembled in a nice clean workshop might not do so well when done in a hurry, dried out alongside a wall. Also these locking compounds aren't cheap, have a shelf life and aren't always readily available when you need them.

Anyway, I asked Norris's to drill a split pin hole and to supply a castellated nut supplied and that was done.