Jump to content

Re packing stern gland


Featured Posts

Hi all. No doubt this has been discussed but the threads I have seen don't have the specifics I am after. My stern gland needs re packing, we are in dry dock in August for blacking and would like it done then. As this is such a crucial area to get right I am unsure whether to get a "proper " engineer to do it or is it such a simple procedure that I could do it myself ? I and pretty good on the tools but have never tackled this before. If I do it myself are there any hints, tips or pitfalls that those of you more experienced than I could point out ? Thank you

Link to comment
Share on other sites

Its very important that every single scrap of old packing is removed. Twice I've had to see to stern gear where the owner hadn't done so. Bits of old packing forced down between shaft and bearing, seized and wore the shaft, burn out PRM 150 gearboxes clutches and busted the drive plates. I'd also smear every packing ring with your stern tube grease before inserting.  I don't recomend the single length spiral method at all.

Edited by bizzard
Link to comment
Share on other sites

10 minutes ago, bizzard said:

Its very important that every single scrap of old packing is removed. Twice I've had to see to stern gear where the owner hadn't done so. Bits of old packing forced down between shaft and bearing, seized and wore the shaft, burn out PRM 150 gearboxes clutches and busted the drive plates. I'd also smear every packing ring with your stern tube grease before inserting.  I don't recomend the single length spiral method at all.

Jolly good advice,I do the same except I use 3 in one oil on the Packing rings,it reduces heat while the Packing is Bedding in and polishes the Shaft.

Stern Glands are perfect when they run cool with Zero drips.

Link to comment
Share on other sites

1 minute ago, cereal tiller said:

Jolly good advice,I do the same except I use 3 in one oil on the Packing rings,it reduces heat while the Packing is Bedding in and polishes the Shaft.

Stern Glands are perfect when they run cool with Zero drips.

Good plan CT.   RLWP ended up with one of the PRM boxes to recondition after one of the disasters I mentioned.

Link to comment
Share on other sites

1 hour ago, colmac said:

Thank you for the replies so far. Will probably tackle it myself. I have 6 days in dry dock to play with once the 2 packing is done.

If you do it in dry dock for goodness sake check it several times after the boat has been refloated. If you do not you will not know you cocked it up until the boat sinks - that's why I do it afloat.

  • Greenie 1
Link to comment
Share on other sites

To expand on what TB says, if you do it afloat you will know if it's a total cockup as the water will keep coming in after you have added all the packing.  If you do it with the boat out of the water you might not notice until the boat is fully floated.  Then you will have to pay again to take the boat out of the water.  And should you forget in the excitement of refloating to make several checks on the stern gland, the boat could sink overnight.  Checks need to be done with shaft turning ahead and astern.  The gland or pusher should be gently nipped up until leakage just stops or is reduced to a slow drip.  If overtightened the packing will burn and the shaft may be scored.  I'm lucky on my boat that the leakage is nigh on zero; just a few drops a day when cruising and nothing when stationary.  Check that the greaser is functional and supplying grease to the stuffing box with no blockages or pipe leaks while the whole thing is in pieces.  

Good luck.

Link to comment
Share on other sites

I did mine last week. I took out three rings using a pick tool and could then feel the tool scraping on metal. I checked with a mirror and everything was gone. What worried me was there was no water coming in. 

I've replaced with new packing but I'm still a little surprised that water didn't rush in once the packing was removed. 

Link to comment
Share on other sites

5 minutes ago, Cheshire cat said:

I did mine last week. I took out three rings using a pick tool and could then feel the tool scraping on metal. I checked with a mirror and everything was gone. What worried me was there was no water coming in. 

I've replaced with new packing but I'm still a little surprised that water didn't rush in once the packing was removed. 

Mine was the same - the grease will keep the water out at least when the prop is not turning.

My favourite bit on Tony's website is as follows: "I have yet to see a stern gear so badly worn that the bilge pump had to be kept running. In most cases I would say you would have at least half an hour of leaking before you have to think about pumping the bilge."

Link to comment
Share on other sites

12 hours ago, Cheshire cat said:

I did mine last week. I took out three rings using a pick tool and could then feel the tool scraping on metal. I checked with a mirror and everything was gone. What worried me was there was no water coming in. 

I've replaced with new packing but I'm still a little surprised that water didn't rush in once the packing was removed. 

This is not unusual, particularly if you operated the greaser as much as you could before starting.

Even on stern gear with a bit of wear I have had not a drip get through whilst all the packing was out.

Link to comment
Share on other sites

11 hours ago, Richard10002 said:

the gland to feel as warm as a freshly brewed cup of tea when the proposed is turning - not too hot to keep your hands on though.

You must like tepid tea!  I can't hold my teacup except by its handle!

Link to comment
Share on other sites

1 hour ago, mross said:

You must like tepid tea!  I can't hold my teacup except by its handle!

I don't like tea :) I was actually repeating some advice I got about 10 years ago. Which is why I added the not too hot bit. Perhaps I should say coffee - I like my coffee drinkable from the moment it's brewed, whereas tea drinkers seem to have a desire to keep testing to the point where it doesn't burn their lips :)

Anyway, the gist is clear.... I think? 

The reason I like to see regular drips is that, if there are no drips, there is no visual way of knowing that the packing isn't too tight.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.