Stern Glands

[ExSurveyor]

Today's technical questions,

On the Sheerline 740 I have a stern gland that has a water pipe connected to it as in the photo.

 

There is water dripping constantly every few seconds regardless of the tap being turned on or off.

1, If I tighten up the stern gland until it drips once a minute will that sort the issue as I would normally expect it to.

2, What is the purpose of the water feed and where does it cool.

3, Where does the water feed usually originate from and where does it exit once in the stern gland

4, Is the problem due to a faulty on off tap ( yellow )

 

 

Second stern gland.

On Whitey we have a similar stern gland but without the water cooler and no grease feed that I had before on a previous boat. 

Until recently the gland has dripped on schedule. The packing is about 6 years old. This inspection I noticed it has stopped dripping altogether. I have slackened the fitting and spun the prop, I now have a bit of a water weep but no drip.  Whitey tends not to have regular long runs.

Any thoughts or suggestions please.

 

[Smoggy]

The water feed is usually fed from the raw water but exactly where from will depend on your engine cooling system, it may not even be a water feed but a vent pipe just going up above the water line to stop air getting trapped in the stern tube(follow the pipe to find out).

The drip you see will be river water coming up the stern tube.

[Meantime]

The pipe will be a feed from the raw water pump. I don't see a greaser anywhere, so it must be water cooled. 

The cutlass bearing at the other end of the stern tube will always let water past and therefore only the stern gland packing will stop that water entering the bilge. 

Turning the tap off will therefore only stop the cooling, not stop the drip.

With no greaser and only water cooling I'd be weary of over tightening the stern gland.

[ExSurveyor]

I suspect it hasn't been adjusted in a few years. It has had more use this month than the previous four year.

My confusion was is the drip related to the water supply and did that mean the tap was faulty as it continued after turning the tap off.

I will nip the gland up a bit and try to find the origin of the pipe.

Must remember to turn the cooler tap back on 😁.

[Meantime]

Just now, ExSurveyor said:

I suspect it hasn't been adjusted in a few years. It has had more use this month than the previous four year.

My confusion was is the drip related to the water supply and did that mean the tap was faulty as it continued after turning the tap off.

I will nip the gland up a bit and try to find the origin of the pipe.

Must remember to turn the cooler tap back on 😁.

My boat has both a raw water feed, which I suspect does very little and it did have the screw down cap greaser, since replaced with a remote stern greaser that gets half a turn once or twice a week.

The cutlass bearing normally has longitudinal cuts along it that let's water through.

[MargeandParge]

We have a raw water pipe fed by a scoupe fitting in the Hull and the cutlass bearing that cools two double lip seals that you manually squeeze grease into every 200 hours or in our case every time we moor for the night. A little on the shaft just above the inner seal for good measure as when we bought the boat it dripped . I replaced the seal and cutlass bearing and touch wood all good.

Kindest Regards Marge and Parge 

 

[MargeandParge]

Having made the above post it must be seal friendly silicone grease.

Kindest regards Marge and Parge 

[ExSurveyor]

Thanks for the advice, I will have a tinker tomorrow.

Any thoughts on the second part ?

 

"Second stern gland.

On Whitey we have a similar stern gland but without the water cooler and no grease feed that I had before on a previous boat. 

Until recently the gland has dripped on schedule. The packing is about 6 years old. This inspection I noticed it has stopped dripping altogether. I have slackened the fitting and spun the prop, I now have a bit of a water weep but no drip.  Whitey tends not to have regular long runs."

Any thoughts or suggestions please.