Stick it!!

[Opener]

My prop shaft runs through a bearing bolted to a cross-member/bulkhead - see out-of-focus picture for the general idea.  Must be an old picture 'cos it shows the grease nipple in place.  I managed to clamp one grease gun to the nipple and, in removing it, ripped the nipple out along with a piece of the surrounding metal.  So, how to fix?  From recollection, the bearing housing surrounds the shaft so must have been fitted onto the shaft before the shaft and prop were installed (Probably).  Can't remove it to work on it - will have to do it in situ.

There is a bit of thread left so I have in mind to use some of that liquid/similar metal in a tube/tin/why.  The existing nipple is quite short - maybe I could get one with a longer reach and build up a shoulder around the neck.  The question is:  what do you think?  subject to degreasing, depainting and roughing, would it take?  What brand do you have experience of?  Source?  I'd use a push grease gun in future which does not clamp onto the nipple.

Thanks guys

 

[blackrose]

Why don't you post a close up picture of what it looks like now with damage? You might get some more useful answers. Otherwise we're just imagining what the damage looks like and how to fix it.

[Ex Brummie]

From your description, without seeing a picture of the damage, could you just seal up the damaged hole, and drill a new hole, and tap it to  take a new nipple?

[dmr]

2 minutes ago, Ex Brummie said:

From your description, without seeing a picture of the damage, could you just seal up the damaged hole, and drill a new hole, and tap it to  take a new nipple?

But quite difficult to do without getting some swarf into the doings.

 

Could just poke some grease directly into the bearing with your fingers for now, then replace the whiole thing next time you are in the drydock (remove rudder and slide shaft outwards enough to remove the bearing)

 

...............Dave

[CV32]

If you decide to poke some grease in, could you not use a mega large jubilee clip or similar to keep the hole covered until you get the chance to repair properly in dry dock - just thinking about keeping the hole clean and stopping any unwanted grit or dirt.

[ditchcrawler]

When you pumped grease into that did you actually get any come out of the bearing race, between the bit of steel on the shaft and the bit of steel in that casting? Most of those bearings are actually sealed for life 

Just now, ditchcrawler said:

When you pumped grease into that did you actually get any come out of the bearing race, between the bit of steel on the shaft and the bit of steel in that casting? Most of those bearings are actually sealed for life 

 

[Tam & Di]

I imagine from what you say that the grease nipple tore out when you tried to remove the grease gun, and rather than simply stripping the thread (either on the nipple or from the bearing) it pulled a plug of metal with it, but there is still some of the internal thread at a lower level. If that is the case then you might indeed find a nipple with a longer thread that will hold within what remains. The problem then would be getting the whole thing perfectly clean in order to use any sort of filler to give additional strength.

There does still remain the question of why it would pull out in the first place - I've never heard of that happening, unless pehaps the grease gun was really firmly attached and you forced the whole thing sideways to try to remove it. Another possibility is that it was a sealed bearing and the grease pumped in created excess pressure which made the nipple liable to failure, but in that case I can't see why there would be a nipple there in the first place.

It is certainly something you need to solve one way or another - a few pennyworth of grease is far cheaper than the cost of a replacement shaft.

 

Tam

[BEngo]

Ditchcrawlers post is relevant, but if not:

I would bet that , if you can get the rudder out of the way, the shaft will slide back far enough to remove the bearing.  You will have to disconnect the gearbox coupling and remove the half coupling from the shaft, then find and remove the grub screw(s) that fasten the shaft to the bearing.  A jubilee clip or cable tie round the shaft will stop it disappearing out of the stern tube by accident.

Once you have the bearing off drill it and tap for  a larger size grease nipple thread.  You could even fit a hexagonal slide over grease nipple.  They are easier to use and less likely to come out again.  You will need a suitable/modified  grease gun, of course.

 

N

 

[gbclive]

A while back, after breaking off a grease nipple, I purchased one of these - a G.Coupler.

 

https://www.amazon.co.uk/gp/product/B0133NDH6E/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

 

Easy and quick to use and it’s especially useful where tight access limits tilting the coupler to one side in order to unlock from the nipple.

[John Hartley]

Check the underside of the bearing housing as a lot f older ones had two grease nipple holes. To make access easier.

 

[Slim]

IF I'm seeing correctly it looks as if the bearing is clamped to the shaft with a couple of grub screws or similar. If so read on, if not ignore hereafter. The half coupling to the R & D flexible should split easily. Once this is done and the grub screws mentioned above eased off wind down on the gland greaser , ease off the gland pusher. The shaft should slide back towards the rudder. If you put the rudder hard over there should be more than enough space for the shaft to drop back sufficiently to clear the bearing in question. For peace of mind clamp a jubilee on the shaft. When reassembling I suggest you repack the stern gland. It can easily (and safely) done afloat.  

[Opener]

2 hours ago, blackrose said:

Why don't you post a close up picture of what it looks like now with damage? 

Love to be there but I'm three hours away - using lockdown to worry about all the things that need doing......

1 hour ago, dmr said:

But quite difficult to do without getting some swarf into the doings.

 

Could just poke some grease directly into the bearing with your fingers for now,

Partly why I've procrastinated for so long - and my fingers are not narrow enough to get down the hole.  Oh!, see what you mean.  I have been trying to force grease in by putting a dollop on the hole then pressing hard with a Mk 1 digit.

1 hour ago, CV32 said:

If you decide to poke some grease in, could you not use a mega large jubilee clip 

Interesting idea - might go down that road for the time being.

 

1 hour ago, Tam & Di said:

I imagine from what you say that the grease nipple tore out when you tried to remove the grease gun, and rather than simply stripping the thread (either on the nipple or from the bearing) it pulled a plug of metal with it,

unless pehaps the grease gun was really firmly attached and you forced the whole thing sideways to try to remove it.

Spot on diagnosis - good quality grease gun from way back in my car enthusiast days - obviously designed to get a good grip on the nipple and not let go whilst pumping grease.  Probably anticipated steel nipple screwed into steel component with enough strength to survive removal of the gun.

 

2 hours ago, Ex Brummie said:

, and drill a new hole, and tap it to  take a new nipple?

Seemed like the obvious solution but I wasn't so much worried about swarf as stopping at the right point to avoid drilling a nice neat hole through the shaft as well.  Assume there would be at least a small gap between the bearing and the shaft but how big a dent/hole in the shaft would cause a weak point - the shaft must be subject to quite some twisting firce when changing direction/starting/stopping.

 

1 hour ago, BEngo said:

 

I would bet that , if you can get the rudder out of the way, etc, etc

 

Looks like that could be the ultimate solution but no-one has addressed the 'stick it together' option.  Has nobody used 'instant metal'  I think there is enough thread left in the hole to position the nipple - just not enough to hold through the rigors of greasing.  Reinforcing what is left looks more attractive than complex engineering solutions at the moment.

 

27 minutes ago, gbclive said:

 I purchased one of these - a G.Coupler.

 

Interesting - but expensive solution to my two minutes of stupidity...........

 

18 minutes ago, John Hartley said:

Check the underside of the bearing housing as a lot f older ones had two grease nipple holes. To make access easier.

 

Whaaaat! - it could be that simple???????  Bugger!!

 

6 minutes ago, Slim said:

IF I'm seeing correctly it looks as if the bearing is clamped to the shaft with a couple of grub screws or similar. If so read on, if not ignore hereafter. 

 

Apart from the question about filler/metal paste/whatever, I think step one is going to be a careful measurement to assess whether the shaft will go back far enough to clear the bearing  and permit fitting a new nipple without drifting gracefully to the canal bed.

In the meantime i'll just sit here and worry about it...........

Cheers and thanks to everyone for your comments - hope I've distracted you for at least a few minutes...............

[Ray T]

1 hour ago, BEngo said:

Ditchcrawlers post is relevant, but if not:

I would bet that , if you can get the rudder out of the way, the shaft will slide back far enough to remove the bearing.  You will have to disconnect the gearbox coupling and remove the half coupling from the shaft, then find and remove the grub screw(s) that fasten the shaft to the bearing.  A jubilee clip or cable tie round the shaft will stop it disappearing out of the stern tube by accident.

Once you have the bearing off drill it and tap for  a larger size grease nipple thread.  You could even fit a hexagonal slide over grease nipple.  They are easier to use and less likely to come out again.  You will need a suitable/modified  grease gun, of course.

 

N

 

Once you have sorted out the bearing an alternative would be to fit a greaser similar to the stern tube, saves a lot of hassle. Before and after.

The rust in the channel has since been treated and re painted.  

 

It is fairly straight forward to release the prop shaft and move it aft, last picture.

Edited April 18, 2020 by Ray T

[Tam & Di]

24 minutes ago, Ray T said:

Once you have sorted out the bearing an alternative would be to fit a greaser similar to the stern tube,

 

 

Beaten to it by Ray. A remote supply of grease with a turn screw will at least reduce the strain when you do manage to fix the immediate problem.

 

Tam

[ditchcrawler]

26 minutes ago, Ray T said:

Once you have sorted out the bearing an alternative would be to fit a greaser similar to the stern tube, saves a lot of hassle. 

But does it actually put grease into the bearing race

[Ray T]

5 minutes ago, ditchcrawler said:

But does it actually put grease into the bearing race

Yes. I use lithium grease not waterproof grease as used for the stern tube. e.g. https://www.ebay.co.uk/itm/Granville-Multi-Purpose-LM2-Lithium-Grease-Quality-Lubricant-Protects-500g-Tin/392270710627?hash=item5b55280763:g:Kr4AAOSwsRlcpMdH

 

If it didn't work I would have dismantled it!

Edited April 18, 2020 by Ray T

[bizzard]

Its probably still full of grease. I'd just block the hole up and I bet it'll see you out. Look at car wheel bearings, just a smear of grease on them, mostly sealed for life and they run forever at high speed. 

[MtB]

10 minutes ago, bizzard said:

Its probably still full of grease. I'd just block the hole up and I bet it'll see you out. Look at car wheel bearings, just a smear of grease on them, mostly sealed for life and they run forever at high speed. 

 

I agree, it's one of those non-problems. Most bearings like that on boats never get greased over the whole life of the boat, I'd bet. I've never seen one fail. Their work is very light duty too, compared to a car wheel bearing. 

[Slim]

1 hour ago, Opener said:

Love to be there but I'm three hours away - using lockdown to worry about all the things that need doing......

Partly why I've procrastinated for so long - and my fingers are not narrow enough to get down the hole.  Oh!, see what you mean.  I have been trying to force grease in by putting a dollop on the hole then pressing hard with a Mk 1 digit.

Interesting idea - might go down that road for the time being.

 

Spot on diagnosis - good quality grease gun from way back in my car enthusiast days - obviously designed to get a good grip on the nipple and not let go whilst pumping grease.  Probably anticipated steel nipple screwed into steel component with enough strength to survive removal of the gun.

 

Seemed like the obvious solution but I wasn't so much worried about swarf as stopping at the right point to avoid drilling a nice neat hole through the shaft as well.  Assume there would be at least a small gap between the bearing and the shaft but how big a dent/hole in the shaft would cause a weak point - the shaft must be subject to quite some twisting firce when changing direction/starting/stopping.

 

Looks like that could be the ultimate solution but no-one has addressed the 'stick it together' option.  Has nobody used 'instant metal'  I think there is enough thread left in the hole to position the nipple - just not enough to hold through the rigors of greasing.  Reinforcing what is left looks more attractive than complex engineering solutions at the moment.

 

Interesting - but expensive solution to my two minutes of stupidity...........

 

Whaaaat! - it could be that simple???????  Bugger!!

 

 

Apart from the question about filler/metal paste/whatever, I think step one is going to be a careful measurement to assess whether the shaft will go back far enough to clear the bearing  and permit fitting a new nipple without drifting gracefully to the canal bed.

In the meantime i'll just sit here and worry about it...........

Cheers and thanks to everyone for your comments - hope I've distracted you for at least a few minutes...............

Obviously you don't want shaft/prop to slide out. Hence the jubilee clip for reassurance. It's a standard practice on offshore boats and is left on. A hand down the weedhatch will give a clue as to space. A bit of wood down the hatch would give added security.  

[bizzard]

8 minutes ago, Mike the Boilerman said:

 

I agree, it's one of those non-problems. Most bearings like that on boats never get greased over the whole life of the boat, I'd bet. I've never seen one fail. Their work is very light duty too, compared to a car wheel bearing. 

Also rear wheel drive articulated propshafts sealed centre bearings and they revolve at about 8 times the speed of a road wheel.

[bizzard]

My car is rear wheel drive and has a transaxle at the back, which ,means the propshaft continually spins whether in gear or in neutral. Its bearing in the rear of the engine clutch bell housing continually spins with the shaft, the bearing is a sealed for life, and its 33 years old now, still silent.

[Tracy D'arth]

A lot of worry about nothing.

 

The shaft will not fall out, it will hit the sideways rudder first.

The bearing runs very slowly compared with its design brief, it will last you out if it is never greased again. Most bearings have been supplied for years for zero maintenance.

You can drill with impunity if you want to tap and fit a nipple, you will never drill through the outer raceway of a bearing never mind the inner raceway and certainly not the shaft.

 

Just carry on boating, it won't wear out or seize up for as long as you will care.

[Bee]

https://wireropeshop.co.uk/wire-store/index.php?main_page=product_info&cPath=1_63_265_266&products_id=1202&zenid=v59ktlpmifunm0t3ghusucvl20 What Tracy says above is right but if you can get that left hand thread thing in the link to bite it will unscrew the remaining bit in the hole

[bizzard]

Chinese bearing will be full of glease...

[Opener]

OK - what is WRONG with you guys!!!  Everyone is coming up with sensible, practical and proper engineering solutions.  But, what about MY stupid idea as a temporary fix?  Clean up/degrease area, roughen and build up a shoulder around the nipple - will it hold and what brand should I use?

I take the point about there probably being enough lubricant in the bearing to last but, if so, why is there a nipple on it?  Is that just to confuse amateurs like me?

Thanks Bee - the nipple actually came out clean - the only good point about the whole fiasco.

OK Tracy - if i'm not going to drill through the raceway, is there any point in drilling in a new location at all?  Do you reckon there will be an opening at the nipple gallery but only there?

I'd probably leave well alone, as widely suggested, but I do get a tortured metal-on-metal scream at certain revs under drive which I haven't tracked down yet - a bit dodgy sailing alone with the cruiser deck boards open - may have to stick the crew down there with the hatches closed to do a definitive check.

Ain't boating fun!