Help! - inboard shaft seized

[Guest]

Hi All

 

My inboard shaft seizes after few seconds of running. If I stop and wait for few minutes, it spins again for only few seconds and then seize again.

 

- Is this problem with stuffing box?

- Do I need to install packing? Is it safe to install in the water?

- Can I adjust stuffing box ring to adjust the dripping rate?

 

As you can tell, I am a novice sailor and I've had my yacht for about 2 years now.

Previously I was able to get the shaft going with few injections of grease to the stuffing box. The trick doesn't work anymore.

 

After research and readings online. If my observation is right, the shaft is seized because the water is not dripping anymore because the ring is too tight and probably it's due for a new packing for the stuffing box.

 

I've never done anything with stuffing box before and I don't have any gut to install packings while in the water. In the article, I learnt that I can adjust the tightness of the ring and allow the water to drip. I am thinking this may help the shaft from seizing and I can get my yacht to a hard for maintenance.

 

I really need your help. It would be awesome if anyone can instruct me what to do.

 

I've attached the photo of the stuffing box. I admit this not the pretties part of my yacht.

 

Many thanks in advance.

[Guest]

Hey Emlo,

The first thing to do is take a deep breath and realise that the end of the world hasn't acutally arrived.

The second thing to do is realise that this little problem is out of your sphere of expertise yet is a crucial part of your boat's water tight integrity so do not faff about taking advice from a bunch of forum experts (except mine, I actually make my living on this sh*t).

The third thing to do is find out about Denso Tape and learn that this sticky, gooey, bloody awful stuff, when applied correctly can save many a fine craft from descending to Davey Jones's fun park.

In all seriousness, if it is a shaft packing issue, then you need good (not necessarily expensive) advice on how to correct it but it can be easily solved in the water. Yacht club membership will get you the sort of advice and help you need at a lot cheaper than my hourly rate.

If it is a shaft bearing issue then you are faced with a haulout unfortunately.

Post updates so we follow.

[too_tall 15]

I strongly second what pwederell has stated - this is outside your area of expertise, and is a vital part of what keeps your yacht afloat. It also is a key safety issue should the shaft seize when you really need the motor to be operational.

Seek out advice from fellow yachties who have experience in this field. I am sure that you can offer them something in return - either a skill you have that they don't, some ethanolic liquid based dietary supplement, or simply offering to pay.

 

If its the packing, then most likely they will show you how to do it, and then its a skill you have learnt. If its the bearing, it could well be an engineers job as shaft or housing could well need attention if its seizing.

 

Are you quite confident that the issue is actually in the gland / bearing area? The prop does not have some rope around it by any chance? ( giving a similar problem to what you experienced before, but from a different cause... )

[Guest]

Thanks for your advices.

 

Just to clarify, what is the major difference between bearing issue VS packing issue.

 

I thought this is related to packing issue because I can spin the shaft and it feels smooth (or normal).

 

The seize only occurs after shaft spins for a few seconds. I thought this is just pure science. Friction on the shaft (no lubrication) cause the shaft to heat up and seizes as the shaft expand from the heat.

 

I can't see any water dripping around the shaft and ring on the stuffing box.

[John B 106]

I expect an old stuffing box to drip after you've operated it. You wind in some grease when you leave the boat.

The flax is compressed to the shaft by a taper between that big nut and the shaft log body itself... maybe its never had enough grease and is rock hard after being left. Maybe barnacles and general marine life have built up and calcified on the shaft at the outboard end and created a 'bearing' which is jamming it up, or at least altering the clearances .

Haul the boat and clear it all out properly or for a first step, perhaps get someone on board who is confident of the setup ,and repack it.

For the future ,its well worth setting up a remote greaser .That is basically a small grease gun and tube permanently hooked up and fitted somewhere more accessible.

[shanson 0]

FWIW

 

I had the same stuffing box in my last boat.

 

it was old, worn and hadn't been repacked in years. When the top was twisted and grease injected if the boat was not in use it never dripped. Once used it would drip constantly, cooling the shaft. this is expected behavior.

 

BTW it was a trivial exercise to replace the knob with a propper grease gun located in a convienant location.

 

SHANE