stern gland nuts very loose

[chubby]

Hello 

Today after tieing up my boat i went to tighten the greaser tap and discovered a large volume of water in my bilge .Far  more than ive seen before . It was alarming .Water was dripping thru the stern gland at i would estimate 1 drip every 3 seconds . I checked the greaser and it was low so i quickly refilled it and gave several turns but it had little effect . So i checked the two nuts either side of the stern gland ( actually there are are 4 . 2 nuts & 2 lock nuts ) . When i checked i found them very loose indeed . I could spin them with my fingers . So , to stop the flow of water into the bilge i tightened them . The port side nuts seemed looser . I did not " nip" them - they needed 4 - 6 turns . The dripping stopped . I was relieved . Then i pumped approx 10-12 litres of water out the bilge using a pela pump . 

This has never happened to my boat before . The only thing different in the last week or so is that the boat has been out the water for blacking . It was on a slipway . Can this have caused them to work loose ? Whilst journeying to the blacking place there was no problem and the bilges were fine . Theyre never bone dry , i always get a little water to bilge pump out , but nothing out of the ordinary . 

This morning when i set off i noticed water in the bilge when doing my pre cruising engine checks but not lots of water and used the bilge pump thru the day . I was shocked to see so much water after i stopped cruising considering how much id been using the bilge pump .

All this has me rather concerned . Im hoping to continue cruising tomorrow as this is my first decent bit of boating in yonks . 

Tomorrow morning i plan to take off the weedhatch and see how easily i can spin the prop by hand . If that is fine & the stern gland is not dripping do i have any reason not to set off - i am worried about making situation worse ? 

Thanks for any thoughts 

cheers

 

[ditchcrawler]

When you get it right make sure you lock the nuts so they can't spin off again. They may have slacked them when you were being blacked to check for play in the propshaft bearing and then "forgot" them.

 

[Neil2]

This happened to me when our boat was lifted out and grit blasted a few years ago.  When she was put back in the water I cruised only a short distance before noticing the engine bilge was several inches deep in water.  Tightening up the stern gland pusher stopped it and it's been fine since.  I mentioned this to the boatyard that did the work (Debdale Wharf) and they claimed that it was nothing to do with the work they did or the lifting out/in, but I'm convinced something happened to loosen the pusher.   I would certainly check this in future as I'm sure you will.  

[bizzard]

More often than not its the studs that unscrew themselves and not the nuts and lock nuts coming undone.

[chubby]

Thankyou for these replies - much appreciated . The blacking was done by myself and i never touched the stern gland at all . As i say during the journey to the slipway all was well . I was very shocked to find the nuts so loose . I think they were 19 mm - i ll check tomorrow . Im going to look at getting two nyloc nut to replace the lock nuts . Ironically i wanted to get the stern gland repacked anyway , just for my own peace of mind - its just getting hold of someone to do it . 

cheers

[bizzard]

5 minutes ago, chubby said:

Thankyou for these replies - much appreciated . The blacking was done by myself and i never touched the stern gland at all . As i say during the journey to the slipway all was well . I was very shocked to find the nuts so loose . I think they were 19 mm - i ll check tomorrow . Im going to look at getting two nyloc nut to replace the lock nuts . Ironically i wanted to get the stern gland repacked anyway , just for my own peace of mind - its just getting hold of someone to do it . 

cheers

Were the nuts actually loose, the lock nuts not locking the main nuts. If so someones not locked em together. As I said, I've usually found its the studs that have unscrewed with the nuts still locked tight together.

[BWM]

Perhaps the packing dried out? Seems unlikely but can't think of another reason. 

[ditchcrawler]

32 minutes ago, chubby said:

Thankyou for these replies - much appreciated . The blacking was done by myself and i never touched the stern gland at all . As i say during the journey to the slipway all was well . I was very shocked to find the nuts so loose . I think they were 19 mm - i ll check tomorrow . Im going to look at getting two nyloc nut to replace the lock nuts . Ironically i wanted to get the stern gland repacked anyway , just for my own peace of mind - its just getting hold of someone to do it . 

cheers

I wouldn't do that as you need to lock the two nuts against each other, I have found you need a thinish spanner to hold the back one to ensure it doesn't nip the gland any more after you have adjusted it.

[AndrewIC]

2 hours ago, bizzard said:

More often than not its the studs that unscrew themselves and not the nuts and lock nuts coming undone.

Got the soggy tee shirt for that one. Put locknuts on to lock the studs into the fixed flange!

[chubby]

Thanks for these replies . I fell very soundly to sleep around 9.30 last night till 06.30  this morning . Exhausting boating innit . 

Bizzard : The nuts were loose - both the nut & lock nut . I could spin them both by hand . The stud however did look to my untrained eye as if it had moved . The two nuts were not " pushed " back against the stern gland pusher . They were both a few mm forward of it . Maybe as you suggest the stud worked loose first followed by the two nuts as they were no longer pressed against the pusher . the two nuts on the port side were looser than the starboard side . 

Ditchcrawler : Very well , i will not look into nyloc nuts . When ive nipped up the nuts in the past i did as you mention . I put one spanner on the furthest back nut to hold it in the adjusted position before tightening the locknut against it with another spanner 

BWM : The boat was out for 8 days in total . Can the grease dry out . 

I ll finish my coffee and get back to the stern shortly

Thanks again for the advice all 

cheers

 

Edited September 7, 2017 by chubby

[chubby]

Ive checked the prop . Its very stiff & cannot be spun by hand . In tightening the nuts last night to stop the heavy dripping the prop has become stiff . 

I dunno if im wasting my time but ive removed the port side stud and nuts . Ive cleaned them with degreaser using a toothbrush and kitchen roll and put them back . The starboard side stud i cannot remove . So ive removed the nuts ,cleaned them and cleaned the stud in situ as best i can .

The pusher has not moved forward whilst i did this . No ingress of water has happened .

Once the stud and nuts are clean is it possible to adjust the pusher forwards towards the bow to loosen it slightly to allow the prop to spin by hand ? This may result in the dripping beginning again at which point i can adjust the nuts to stop this but only tighten as much as necessary in order to leave the prop spinnable ? 

Apologies folks if im barking up the wrong tree here as ive not done any of this before . 

Otherwise , any other suggestions as its a lovely morning to be boating and not sticking my head down into some primevil looking greasy oily swamp of a bilge

Thanks again 

Edited September 7, 2017 by chubby

[Jen-in-Wellies]

Removing the stud may, if anything, make it more likely to come out again in future. It should be screwed in to the fixed part of the stern gland with a dab of thread lock (removable), or stud lock (pretty permanent). There are two places where things can come unscrewed in the gland. The nuts pushing in the movable part of the gland and the studs that are screwed in to the fixed bit. If either move, then the gland comes loose and the drips become more frequent. Too tight and the prop becomes hard to turn, wear of the packing inside the gland increases and you are soon back to drips again. Nylock nuts will work, but are not really as secure as a nut and lock nut, properly locked together using two spanners. When the inner nut is set, run the outer nut down to it, then with a spanner on each put clockwise pressure on the outer spanner and anticlockwise on the inner. This will lock them against each other and against the threads of the stud.

Pressure on each side of the pusher bit of the stern gland needs to be equal.

Jen

[chubby]

an update : The forward half of the pusher has eased forwards . I can shake it a little by hand . The prop spins but it still feels stiff . Its spins but not " freely " - it takes some effort . 

The nuts are loose , not tightend against the forward half of the pusher and not tightened against each other , able to spin freely on the stud . 

Im reluctant to go any further , not that ive any clue what the next step would be . Hopefully the grease from the tap is whats now keeping the water out now that the pusher & nuts  are loose . 

So - any ideas as to what i should do next ? im gonna keep checking the stiffness of the prop every 20 mins to see if it loosens any more 

Thankyou 

 

Jennin wellies - thankyou . Ive only been able to remove one stud . I think Bizzard was right in that the stud worked loose not the nuts . Once ive cleaned it ive put it back and it screws into the rear side of the pusher set up . The prop has loosened slightly now . Will not use nyloc nuts afterall and will do as advised by yourself and ditchcrawler and use the existing nut & lock nut using two spanners . Im not aware of thread lock - all this is new to me . I learn as my boat forces me to learn !! . I have none onboard but will try to get some . Id like all this to be looked at by a boat engineer / mechanic soon along with a seevice and a general look over of the engine mounts , prop alignment etc . Im heading north on the S Grand Union so maybe i ll see if i can get this done in Braunston maybe once im underway again . Part of the reason i removed the nuts altogrther and cleaned them is so that when hopefully the time comes to tighten them again i can ensure that i turn each nut equally and therefore ensure equal pressure on both sides of the pusher as im starting from scratch so to speak . 

Now the forward half of the pusher is looser i did expect water to drip thru . At which point id tighten up only as little as necessary but nothing has dripped thru which i find strange . But then again theres no engine running or prop turning . I can only imagine that the grease from the tap is keeping the water at bay .

Cheers again 

Edited September 7, 2017 by chubby

[bizzard]

Were they proper studs with a bit of blank shoulder between a thread at each end? Or, again more often than not just lengths of threaded rod. Theaded rod is likely to keep coming loose. If studs, tighten them up tight against the blank shoulder. But whichever you have  clean all the threads, male and female with spirit and Lock-tite them in. Sounds like it might need re-packing, a bit of packing may have got squeezed down between the shaft and tube bearing making the shaft too stiff when you perhaps overtightened the nuts. Withdraw the pusher and squirt some oil in there and  more grease before readjusting. When re-tightening the nuts do then equally bit by bit whilst giving the shaft a turn, as soon as it starts to get stiff, stop, run it in gear for a bit, stop and re-check nuts and for leaks, a drip now and then is ok.

[bizzard]

The propshaft might be out of alignment causing over stiffness.

[chubby]

Thankyou Bizzard 

The studs have a shoulder . When screwed into the forward pusher the shoulder sits between the two halves of the pusher set up . 

Ive cleaned all the nuts and studs . I couldn't remove the starboard side stud as it was firmly stuck so i cleaned it with degreaser and toothbrush to clean the threads of muck , grit etc . So all the adjustable bits are clean now .

I will get the stern gland seen to , its just difficult to get someone but im heading North, no idea how far im going and so i ll try to organise something in Braunston maybe - if i can get going again . 

The forward pusher is loose . The nuts are loose but the prop still seems stiff to me . I dunno what im comparing to tho . I have to apply force to the prop to turn it by hand - i wouldn t say it " spins freely " . Im concerned that if its too stiff then this may put extra demand on the engine or prop shaft etc . Forgive me if talking out if my backside - this is new territory for me . 

I shall get some oil and grease into the gap behind the pusher as you suggest and then tighten each nut equally. 

I guess i then turn the engine on and see if water comes thru and adjust each nut equally again . Once water ingress is down to the odd drip i can adjust the locknuts up to the other nuts and secure with two spanners . 

Does this sound correct ? 

Scary stuff for the uninitiated- thanks again 

 

ETA : just seen your prop alignment comment. Id be way out of my checking properly. Ive just given it a " strong yank " & theres seemingly no play in it though im sure theres far more to it than that . 

Edited September 7, 2017 by chubby

[bizzard]

4 minutes ago, chubby said:

Thankyou Bizzard 

The studs have a shoulder . When screwed into the forward pusher the shoulder sits between the two halves of the pusher set up . 

Ive cleaned all the nuts and studs . I couldn't remove the starboard side stud as it was firmly stuck so i cleaned it with degreaser and toothbrush to clean the threads of muck , grit etc . So all the adjustable bits are clean now .

I will get the stern gland seen to , its just difficult to get someone but im heading North, no idea how far im going and so i ll try to organise something in Braunston maybe - if i can get going again . 

The forward pusher is loose . The nuts are loose but the prop still seems stiff to me . I dunno what im comparing to tho . I have to apply force to the prop to turn it by hand - i wouldn t say it " spins freely " . Im concerned that if its too stiff then this may put extra demand on the engine or prop shaft etc . Forgive me if talking out if my backside - this is new territory for me . 

I shall get some oil and grease into the gap behind the pusher as you suggest and then tighten each nut equally. 

I guess i then turn the engine on and see if water comes thru and adjust each nut equally again . Once water ingress is down to the odd drip i can adjust the locknuts up to the other nuts and secure with two spanners . 

Does this sound correct ? 

Scary stuff for the uninitiated- thanks again 

There would be a little resistance when turning the shaft but not stiff stiff. I'd run it in gear for a bit with the gland nuts slackened off whilst the boats tied up, which might ease off the stiffness, before tightening it and cruising away.  Whilst cruising along regularly check and feel the gland for overheating, is should get no more than warmish, not too hot.  The gland might need re-packing. Also propshaft alignment checking, the engine mounting rubbers may have sunk down a bit.

[blackrose]

It's always slightly alarming to find a large amount of water in the bilges. Personally I wouldn't be without one of these in my engine bilge as an early warning system. Just set the sensor height as you wish.

http://www.ebay.co.uk/itm/Water-Leak-Alarm-Flood-Level-Overflow-Detector-Sensor-Alert-Fish-Tank-Kitchen-/182488773559

There are plenty of other more expensive/better quality models on ebay. I've got a few dotted around the boat - in a bowl under the shower drain, next to my water pump which is installed in a washing up bowl. They've alerted me and saved my boat from minor floods a couple of times. I think one in the engine bilge is a no-brainer. They are quite loud and you would hear it above most engines. If you're shocked to see a few litres of water down there, then imagine finding a foot of water in your engine bilge! Better to know about flooding sooner rather than later. 

[rusty69]

We have a bilge pump in a tub beneath the stern gland, turn it on every couple of hours, or get an auto one. 

[chubby]

Thanks again folks . 

Bizzard : Ive just been speaking with a very helpful local boat engineer . He has said almost exactly what you say in your last post . He s advised me not to be scared of it and that there will be resistance from the prop shaft - it wont " spin " as such and effort is required but not force as such .

Blackrose : Thankyou - these i will check out later today .

Rusty : Thats exactly what i do normally when underway . A quick go every 45 mins or hour . Almost nothing comes out . Yesterday more than usual did so i thought there was no prob until i moored up and noticed alot of water in the bilge as turned the greaser tap as i always do once moored up . 

Cheers again . Quick cuppa and back to work 

 

[chubby]

Theyre a helpful bunch of folk arent they - boaters . A chap just went past me to work the next lock and i asked him about my prop shaft , its stiffness etc . He jumped down into my quagmire of a bilge to spin the propshaft & suggested that the effort needed to spin it was as he would expect. I explained that i 'd nothing to compare it to and that it felt stiff to someone who wouldn't know otherwise & he reassured me that the degree of resistance was normal . 

I have since run the engine in gear , forwards and reverse several times . No water dripped thru during about 15 minutes of running time . The stern gland became slightly warm - definitely not hot .

I have tightened the nuts only as much as necessary, followed by lock nuts done with two spanners.

All being well that should be that but i am a little concerned about the port side stud working loose in the first place so i will get hold of this lock tight stuff and get that seen to . 

Thankyou again to all whove helped me . As i say each time i ask for help i am grateful for your willingness to share your knowledge. I daresay all this looks to some like a straightforward job , all easily put right . But im a big believer that one should never judge another persons abilities using thier own as a yardstick . We are all different. To me this was a very daunting task - its where the water that should be outside the boat has an opportunity to enter the boat . Scary stuff . So thankyou for your patience again . 

A quick bit of brekky and i ll head off . I shall report back once i moor up what has happened whilst cruising . 

Another step up the learning curve 

Cheers 

[WotEver]

14 minutes ago, chubby said:

All being well that should be that but i am a little concerned about the port side stud working loose in the first place so i will get hold of this lock tight stuff and get that seen to . 

In the mean time, how did you tighten the stud? One way of doing so is with a small pair of Stilsons on the plain neck. In the absence of those you can lock the two nuts on the other end and then use the locked pair to give good torque to the stud. But don't overdo it, you wouldn't want to damage the threads. 

[matty40s]

It is not scary to repack your own stern gland. You have done most of the stuff already during your fault finding.

[Robert Laws]

2 hours ago, matty40s said:

It is not scary to repack your own stern gland. You have done most of the stuff already during your fault finding.

But you'd do that with the boat out of the water yes?  I know people do it with the boat in the water, after packing in a lot of grease, but I'd never dare.

 

BTW, I'm new here so, 'hello everyone'.

Robert

 

 

[rusty69]

http://www.tb-training.co.uk/10sgear.htm