Stuffing gland maintenance

[AkZuma 1]

Looking for recommendations for getting the prop shaft looked at in Westhaven. We have a Lidgard 29 and the prop shaft has got tight enough to stall the engine. The first engineering company we tried does not want to look at it, so looking for more recommendations.

[K4309 269]

That sounds like a real can of worms. I've never heard of that happening, and I wouldn't want to be finding a suitable engineer to investigate that this close to Christmas.

What sort of stuffing gland is it? Like the standard thing with flax stuffing (square fibre, like hemp with lots of grease) and you pump grease into it every time you've been out?

Why do you think it is the stuffing gland that is stalling the engine?

When was the last time you had a bum clean, and is the shaft, prop and cutless bearing free of barnacles and oysters? i.e. have you had a look underneath and confirmed it isn't something else? 

You haven't just ran over a fishing line have you? They can choke around the cutless bearing and could cause similar symptoms. Especially a bit of net. They will stall an engine and choke up around the prop / cutless bearing. Infact, the only time I've had a laboured and stalling engine I ran over a fishing net combined with seaweed in Falmouth Roads. A diver soon had it sorted.

I'd be keen for other's opinion on here, but I'd be surprised if a cooked stuffing box could stall an engine by itself. It would make loads of heat and stuff, but there isn't enough surface area to overcome the torque on a prop shaft. Shafts do get 'necked' over time too, but that wont cause the issues you have. Normally just make the stuffing gland drip more.

My bet it's something else. If the shaft was completely out of alignment it would cause a hell of a vibration normally, but not stall the engine. How are the engine mounts? Has the engine dropped down? It is possible to break engine brackets (I've broken two on a 35 yr old engine) which cause the engine to drop. All the weight would go on the shaft at the stuffing gland then. It could give symptoms that make you think it is an issue with the stuffing gland. Generally the main symptom is vibration like you have a jack-hammer pounding on your hull as well (very bad vibration) which is a sign of other issues.

Back to the stuffing gland, if you back the nuts off do you get water out, or is it completely dry, i.e. sea water dripping or dribbling out of the stuffing gland? It is possible to cook the stuff inside them. I think basically you have to pull and pry the stuff out with needles and hooks and put some new stuff in. Best done on the hard, as once you get the stuff out water comes in uncontrolled until you get the new stuff in. Very tedious, but a straight forward DIY job.

A haul out might give you some insight into what is wrong. If it's a net or fishing line it is an easy fix. If you need to re-pack the stuffing gland you have to do that on the hard. If it is something more complex you can rule out the first options, but it back in the water to save on hardstand cost, and work out what to do then.

Linking back to your original question, I think it would be challenging finding an engineer at this time of year and with a problem with real scope for not being a simple fix / getting bigger on investigation. That doesn't mean there isn't anyone around, I just don't know of any. 

[Psyche 634]

 You can repack a stuffing box in the water, its been done thousands of times. A friend did one last year for the first time no problems,  plenty of youtube videos out there, the water pressure is very low and a few rags will stop most of the flow so no need to panic when you are doing it! Or do it on the grid to have a good look at the cutlass bearing as well, no need to pull  it out at this stage.

[K4309 269]

2 hours ago, Psyche said:

 You can repack a stuffing box in the water, its been done thousands of times. A friend did one last year for the first time no problems,  plenty of youtube videos out there, the water pressure is very low and a few rags will stop most of the flow so no need to panic when you are doing it! Or do it on the grid to have a good look at the cutlass bearing as well, no need to pull  it out at this stage.

Do you think it's possible an overtight stuffing box could stall the engine? It's not something I've heard of.

[Psyche 634]

Melted goretex, tired 2GM? Who knows?

[waikiore 400]

I have seen this happen three ways 

1 with an overtightened gland -not normal

2 with broken engine mounts -sometimes

3 with Novasteen (Tufnol) type stern bearings machined without enough clearance -or nylon types -they all swell . Vesconite is the only one that doesnt. -Quite common

[AkZuma 1]

Thanks for your feedback on what the problem might be but what I am looking for recommendations for a company that might be able to help. I would rather have have someone ready to go than haul it out and then start looking for someone hence my request for recommendations.

My initial thought was the gearbox had seized. I uncoupled the prop shaft from the gearbox and the prop shaft will turn by hand if you have something to provide a little leverage but it is tight. The engine runs fine even in gear with the prop shaft uncoupled, so I am pretty certain it is something in the shaft and not anything to do with engine alignment etc. It is tight but not seized solid. The problem starting occurring during a monthly engine run and had been fine up until then so not a prop strike and should not be a bent shaft I hope.

Put a camera under the boat and there was some growth and as we can't move we got a diver in to clean it up and check for anything growing or tangled. They cleaned it up but couldn't find anything obvious and said they could turn the prop. That has a bit more leverage than just grabbing the shaft coupling by hand.

I don't know what type of stuffing box it is but it is one I have been putting grease in a few times a year as recommended by my boat builder father in-law who we inherited the boat from. So my assumption at this stage is stuffing box problem or 10 years of grease has solidified around the shaft. Because it is such an unknown I am not comfortable doing anything on the water and was hoping I could tee up an engineer before coming out as a necked shaft or having to replace bearings is beyond me.

We have a tentative date to haul out the week before Christmas as that was all we could get but we will push that out into the new year as I don't want to get stuck on the hard during the great kiwi shutdown. 

Who would have thought finding an engineer would be so hard in the city of sails.

[harrytom 648]

When my friend launched his yacht ,1gm, the gland never dripped and thats a problem,needs to drip for lubrication.Not a stream but dripping every few seconds.1hr motor may get get 250ml?Shouldnt drip when stopped.. Maybe fit a dripless going forward if room?

[Psyche 634]

Before hauling it and ruining xmas, put it on the grid and slide the stuffing box  up the shaft so it rotates with it, that should give you a pretty good idea of whats going on. if you are not comfortable with doing it yourself then get a friend with some experience to help, its really not that difficult. Could be a build up of old hardened grease in the shaft  or as simple as some new stuffing required.  Worst case refit the SB and carry on with plan A

[waikiore 400]

you should be able to turn a 1" shaft in neutral easily with just a finger and thumb , otherwise you are wasting horsepower trying to bend the boat.

 

[AkZuma 1]

3 hours ago, Guest said:

Gordon-All marine 027 542 6104

Mark -021 870 198

Thanks for the referrals, I will follow up with them.

The other thing that makes me suspicious the problem is more than the stuffing box, is that is mounted on a flexible hose. You would assume if the stuffing box was tight enough to stall the engine the hose would twist or deform in some way and they would have to be some powerful hose clamps that hold it all together.

PS Sorry about the delay in response. Being a noob here all my posts need to go via a moderator.