Rudder Packing—again


Bill Kinney
 

This is my update to a former thread on rudder packing for the Super Maramu.

When we needed to replace ours we used standard 3/8” packing, which is a tiny bit smaller than the 10mm size this system was designed for.  As many others have found, installing the packing in the stuffing box is very difficult. The stuffing box is designed to use three rings of packing. The issue I (and many of you!) ran into was the height of three rings was so high that it was impossible to engage enough threads of the plastic nut to tighten it without stripping out the threads.  

I pounded on the packing with a pipe and a 5 pound sledge.  I lubricated it.  I pushed and prodded every what I could thing of, but no love.

Finally in desperation, I took out the top ring of packing and tightened down the nut on the remaining two.  This “kind of” worked.  But no matter how much I tightened the nut it still dripped.  Very slowly, but more than zero.  Another solution was called for.

I resorted to a product I have had good luck with on propeller shafts. A  PTFE putty sold by Western Pacific Trading as “Drip-Less Packing.” Western Pacific Trading is the largest supplier of all forms of packing for small marine shafts in the USA, and is sold through most chandleries. This was the first time I tried their Drip-Less packing on a rudder shaft with its very low speed rotation. The smallest package size is plenty of material for this application.

You install one ring of standard packing at the bottom, pack in some of the moldable packing which comes as a stiff, green putty, and then install a second ring of standard packing on top.  The standard packing rings are there to just hold the putty in place, the putty does the sealing.  Since I had control over how much I added, I could reduce the thickness a bit, and have enough room to engage threads on the nut.

As I expected, it took a couple of times sailing, and re-tightening the nut to fully compress the packing and stop all water intrusion.  But now it seems perfect. That area around the rudder shaft is, as it should be, bone dry.  If my experience using this material on propeller shafts is any indication, it should be very close to a permanent solution.

I believe some people have reported success going down to 5/16 inch packing, then tightening the nut to squash it enough to seal.  I haven’t tried this myself. I was reluctant because if I needed to remove ALL the packing to redo the install, I didn’t want to have to haul the boat, or deal with that amount of water influx. 

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL


Alan Leslie
 

Interesting Bill,

I had this issue some years ago...couldn't get all three rings of packing in and thread the nut.
I put in 2 and it leaked, so I put in a turn of 8mm cord and tightened the nut to stop it leaking. We sailed for a while (actually about 3 months), then finally on haul out, took out the piece of cord and managed to get the third ring in, with some pounding, and it hasn't leaked in 7 years, with no adjustment of the nut needed - yet.
The rudder gland is normally above the waterline, unless the boat is overloaded at the stern, water ingress shouldn't be a major problem.

Cheers
Alan
Elyse SM437


william reynolds
 

Francoise at Amel in Martinique has a great solution. He has designed an extension of the shaft tube which is epoxied and screwed in place. I now can insert 5 -3/8's  packing strips and 6 if I press down hard. I use a 2" sch. 80 PVC pipe to set the packing and don't drive them in too forcefully. I use the gland nut to apply the pressure to stop all leaks. 10m months, lots of bashing and no leaks.
Bill 
Cloudstreet


James Alton
 

Bill,
   I like your solution using the PTFE Dripless packing on the rudder shaft and suspect it will solve your leakage and repacking problem.  I had a customer with a twin screw  Gulfstar who amazingly made a circumnavigation without ever tightening either packing gland on the prop shafts.  Both glands were dripping slightly after the trip but it was not enough for him to worry with apparently.  Both glands were packed with the Teflon impregnated packing with the he Dripless Packing additive.  I have a package of the Dripless additive aboard and will be adding it to the rudder and propellor shaft log at some point but have been getting excellent service with just the PTFE packing and the Amel installed grease gland so not a priority project.   Best,. James Alton,. SV Sueno, Maramu #220


On Sun, Dec 26, 2021 at 8:16 AM, Bill Kinney
<cruisingconsulting@...> wrote:
This is my update to a former thread on rudder packing for the Super Maramu.

When we needed to replace ours we used standard 3/8” packing, which is a tiny bit smaller than the 10mm size this system was designed for.  As many others have found, installing the packing in the stuffing box is very difficult. The stuffing box is designed to use three rings of packing. The issue I (and many of you!) ran into was the height of three rings was so high that it was impossible to engage enough threads of the plastic nut to tighten it without stripping out the threads.  

I pounded on the packing with a pipe and a 5 pound sledge.  I lubricated it.  I pushed and prodded every what I could thing of, but no love.

Finally in desperation, I took out the top ring of packing and tightened down the nut on the remaining two.  This “kind of” worked.  But no matter how much I tightened the nut it still dripped.  Very slowly, but more than zero.  Another solution was called for.

I resorted to a product I have had good luck with on propeller shafts. A  PTFE putty sold by Western Pacific Trading as “Drip-Less Packing.” Western Pacific Trading is the largest supplier of all forms of packing for small marine shafts in the USA, and is sold through most chandleries. This was the first time I tried their Drip-Less packing on a rudder shaft with its very low speed rotation. The smallest package size is plenty of material for this application.

You install one ring of standard packing at the bottom, pack in some of the moldable packing which comes as a stiff, green putty, and then install a second ring of standard packing on top.  The standard packing rings are there to just hold the putty in place, the putty does the sealing.  Since I had control over how much I added, I could reduce the thickness a bit, and have enough room to engage threads on the nut.

As I expected, it took a couple of times sailing, and re-tightening the nut to fully compress the packing and stop all water intrusion.  But now it seems perfect. That area around the rudder shaft is, as it should be, bone dry.  If my experience using this material on propeller shafts is any indication, it should be very close to a permanent solution.

I believe some people have reported success going down to 5/16 inch packing, then tightening the nut to squash it enough to seal.  I haven’t tried this myself. I was reluctant because if I needed to remove ALL the packing to redo the install, I didn’t want to have to haul the boat, or deal with that amount of water influx. 

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL


Bill Kinney
 

Francoise at Amel in Martinique has a great solution. He has designed an extension of the shaft tube which is epoxied and screwed in place. I now can insert 5 -3/8's  packing strips and 6 if I press down hard. I use a 2" sch. 80 PVC pipe to set the packing and don't drive them in too forcefully. I use the gland nut to apply the pressure to stop all leaks. 10m months, lots of bashing and no leaks.
Bill 
Cloudstreet
Extending the shaft tube was going to be my next step if the Dripless packing didn’t work. My plan was to cast an extension in place using JB Weld, or something similar.

 I’d love to see a picture of what yours looks like, because I can’t see how I could extend my tube that far (2.5 to 3 cm?) without making major changes in the alignment of the various parts of the steering gear that seem like they would be complex to sort out.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL


Eric Freedman <kimberlite@...>
 

Bill,

Amel also did mine.

They used my spare packing nut with release on it and laid up the extension. It is a bit longer than 2 pieces of packing.

It is the same diameter as the original stuffing box. They epoxied this assembly to my existing stuffing box.

They also added a few long screws. Works great and there in no problem with the clearance with the ruder quadrant.

Fair Winds

Eric

Kimberlite Amel Super Maramu #376

 

 

 

From: main@AmelYachtOwners.groups.io On Behalf Of Bill Kinney
Sent: Monday, December 27, 2021 4:20 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Rudder Packing—again

 

Francoise at Amel in Martinique has a great solution. He has designed an extension of the shaft tube which is epoxied and screwed in place. I now can insert 5 -3/8's  packing strips and 6 if I press down hard. I use a 2" sch. 80 PVC pipe to set the packing and don't drive them in too forcefully. I use the gland nut to apply the pressure to stop all leaks. 10m months, lots of bashing and no leaks.

Bill 

Cloudstreet

Extending the shaft tube was going to be my next step if the Dripless packing didn’t work. My plan was to cast an extension in place using JB Weld, or something similar.

 I’d love to see a picture of what yours looks like, because I can’t see how I could extend my tube that far (2.5 to 3 cm?) without making major changes in the alignment of the various parts of the steering gear that seem like they would be complex to sort out.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL


James Alton
 

Bill,

   I don't think that you would need to extend the shaft tube very far to accomodate one additional packing ring.  Fiberglass/epoxy would be far stronger than the JB weld, especially if you prepared the surfaces of the original fiberglass structure to bond your extension to.  You could screw your extension tube "mold" into the existing threads after preparing all surfaces.  Wax your mold well with a mold release wax and make the wax thick at the bottom to insure no epoxy can drool down the tube.  Then mix up a thickened epoxy, using collodial silica, maybe adding some finely milled fiberglass.  Coat to fill the threads in your mold filling all voids, then wrap many layers of 10 ounce cloth cleanly cut so that you don't have a mess.    Build the thickness you want for the tube extension then using more thickend epoxy fair the new tube into the original fiberglass structure and fiberglass the extension tube to the original structure lapping perhaps 2" onto the original structure.  10 layers would probably do it.  This way your extension tube is not relying on just a bond to the top of the original structure, you will have a significant and strong attachment.  The glass fiber wrapped around the mold will form a strong tube that can withstand considerable tension from tightening the nut and should not crack on you.  You may need 50 more more layers and if needed do this layup in stages, curing the epoxy and preparing the surface.  I often use the West 105 Epoxy resin for these types of jobs but a harder/stronger resin might create stronger threads.  Regardless of the epoxy resin, I would do a post cure per the epoxy resin manufacturers recommendation to raise the glass transition temperature and improve the hardness and strength at room temperature.  On the other hand, if your current solution with the Dripless packing has done the trick, maybe doing nothing is an even better solution!

Best,
James Alton
Recovering in Marmaris Turkey aboard SV Sueno


-----Original Message-----
From: Bill Kinney <cruisingconsulting@...>
To: main@AmelYachtOwners.groups.io
Sent: Tue, Dec 28, 2021 12:20 am
Subject: Re: [AmelYachtOwners] Rudder Packing—again

Francoise at Amel in Martinique has a great solution. He has designed an extension of the shaft tube which is epoxied and screwed in place. I now can insert 5 -3/8's  packing strips and 6 if I press down hard. I use a 2" sch. 80 PVC pipe to set the packing and don't drive them in too forcefully. I use the gland nut to apply the pressure to stop all leaks. 10m months, lots of bashing and no leaks.
Bill 
Cloudstreet
Extending the shaft tube was going to be my next step if the Dripless packing didn’t work. My plan was to cast an extension in place using JB Weld, or something similar.

 I’d love to see a picture of what yours looks like, because I can’t see how I could extend my tube that far (2.5 to 3 cm?) without making major changes in the alignment of the various parts of the steering gear that seem like they would be complex to sort out.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL