Rudder stuffing box

[AquaAura]

New to the forum and this is my first post. We are in the process of buying a 42 Hershine and this was about the most significant thing I found on the survey which is the starboard rudder box corrosion and very slow leak even with the packing tightened all the way. Question to you is how bad do you think this is and any ideas where to find the replacement box? Do you think it needs replacement or just clean and repack at next haul out?

The port box looks a little better but still has corrosion however does not leak.

 

[CharlieO.]

You may be able to do a repack without haul to slow or eliminate the leak but I would be hesitant to work on that in the water though. It is pretty ugly. Can't you have it addressed in your offer?

 

[Gdavid]

Whether the stuffing box requires replacement depends on how it is constructed. Look at these examples of two rudder stuffing boxes.

The example on the left mounts the primary mounting flange inside of the hull and the sealing surface is below that flange and the inside of the hull. If yours is constructed like the unit on the left, I would say that it needs to be replaced as the plates look completely eroded in the corners where the nuts are located.

The example on the right, the primary flange is outside of the hull, seals to the outside of the hull and the thinner plate is a backing plate that mounts inside of the hull. If it is made like the unit on the right, you might just need to replace a backing plate, something you can make or have made.

In either case it should be removed from the hull, cleaned up and re-bedded at a minimum.

 

[mvweebles]

I zoomed-in (see attached). This fitting is wasted. Did the surveyor have any concerns about corrosion or bonding?

Buck Algonquin makes stuffing boxes with flange-mounted bases, but I could only find ones with single large gland nut vs the 'winged' press plate style.

Assuming you haven't said "I do" yet on the deal, I would ask for this to be repaired vs a survey credit. Type of thing that could have an iceberg beneath it......

Good luck - please update. Definitely curious to see how this goes.

Peter

 

[Portage_Bay]

Be prepared for some work on the rudder posts as well. I just had my rudder packing boxes done and it took a bit of TLC on one of the posts by the yard's machinist. If the posts are bronze probably not too bad. Definitely do both port and starboard at the same time and given the wastage mvweebles point out don't wait too long or go too far before you address the problems.

 

[AquaAura]

I don't want the current owner to fix anything and we haven't finalized the deal yet either. I would prefer money off and I will address this myself when it gets hauled out after summer.

I am definitely not doing this while it's in the water.

From under the boat I do not see any bolts however I can now see that the rudder mount is recessed into the boat bottom and the bolts from underneath are covered with I'm guessing a filler then bottom paint as underneath is completely smooth.

 

[mvweebles]

I don't want the current owner to fix anything and we haven't finalized the deal yet either. I would prefer money off and I will address this myself when it gets hauled out after summer.

From under the boat I do not see any bolts so I am not sure where those studs are coming from that has the nut on it.

I'd have no idea how much money to knock-off on this one which is why I'd rather have it repaired vs a survey credit. I do not normally go immediately to disaster-diagnosis, but I have never seen corossion like that and fear the rudder post could have some crevice corossion too (as Portage Bay says). Without a decent diagnosis, I wouldn't be too eager to venture too far. The flange plate is swollen (rust???) and the retaining nut has been tightened deep into what was once solid metal suggesting there may not be much structure left. Who knows - maybe a tapping a log with your rudder or wrapping a line might be a tipping point.

Keep your SeaTow current; and toss a can of SplashZone in your laz just in case.

Good luck -

Peter

 

[AquaAura]

I zoomed-in (see attached). This fitting is wasted. Did the surveyor have any concerns about corrosion or bonding?

Buck Algonquin makes stuffing boxes with flange-mounted bases, but I could only find ones with single large gland nut vs the 'winged' press plate style.

Assuming you haven't said "I do" yet on the deal, I would ask for this to be repaired vs a survey credit. Type of thing that could have an iceberg beneath it......

Good luck - please update. Definitely curious to see how this goes.

Peter
View attachment 139530

I also can not find the winged style either. I think as posted above it is the backing plate style so I can remove the backing plates clean and rebed then replace the packing and re secure.

 

[Gdavid]

I don't want the current owner to fix anything and we haven't finalized the deal yet either. I would prefer money off and I will address this myself when it gets hauled out after summer.

I am definitely not doing this while it's in the water.

From under the boat I do not see any bolts however I can now see that the rudder mount is recessed into the boat bottom and the bolts from underneath are covered with I'm guessing a filler then bottom paint as underneath is completely smooth.

The heads to the hardware may have been recessed into the hull and glassed or faired over and therefore not visible. Is the boat currently on the hard?, can you snap some pictures or did the surveyor take some of the hull at the rudders?

 

[AquaAura]

We just pulled it for survey and it's back in the water. I have many photos I took. You can see the rudder in this photo.

 

[AquaAura]

Those are salt deposits that are making the bolt look like it's pressed into the backing plate.

 

[mvweebles]

We just pulled it for survey and it's back in the water. I have many photos I took. You can see the rudder in this photo.

GDavid posted two pics of a stuffing gland above. This looks like the first one, likely cut-down a but so 1/2" extends below hull. The bolt-heads would be buried and glassed-over, same as is typically done with sea-cocks.

The layers on the base plate sure look like steel/rust. Are you pretty sure it's bronze? It should be, but the flaking sure looks like something ferrous even though that would be a no-no in this application. If non-magnetic, I'd feel better about waiting to do the work.

What did your surveyor say? Any concerns? He's there and can poke it with an awl.

Peter

 

[Gdavid]

It looks like the example to the left in the photos I posted earlier, the two bolts versus single large nut style really doesn't matter (to my knowledge).

I would want it repaired prior to going back into the water, especially because this rudder does not have any support at the bottom. If I was doing the work myself, I would plan for $500-1000 and two days but budget $2K and two weekends, assuming the boat is already out of the water. If I was hiring the work out, I would double that.

In my opinion (discounted), any hardware on a ~20 year old boat is due for re-bedding and inspection anyway, the fact that the fitting is degraded and requires replacement is not shocking at all, it does not appear to be bonded to the cathodic protection of the boat. I would try to bargain for $2-4k off the price and use the funds to replace both, as well as re-bed any other hardware that has not been documented to be refreshed. Have the surveyor take a look when you are done and you will be better positioned when shopping insurance.

 

[mvweebles]

..... If I was doing the work myself, I would plan for $500-1000 and two days but budget $2K and two weekends, assuming the boat is already out of the water. If I was hiring the work out, I would double that.
.....

Plus haul and lay-days.....plus parts/fasteners/bedding/bonding/epoxy/etc.. $4k for yard feels about right since DIY-tolerant yards are rare.

Gdavid- you always have a decent handle on stuff like this. What do you think the chances of crevice corrosion to the rudder post as Portage Bay experienced?

Peter

 

[Portage_Bay]

You asked for opinions. Mine is this is potentially very serious and not worth taking any chances.

Before you decide to cruise farther than the soonest possible haul out, you did say she's back in the water? Consider the likely and possible failures. Think how you will handle said failures. I see the possibility for loss of steering and or serious flooding. But that's just me looking at a few pics.

What I see is twin rudders tied together with the steering ram attached to one rudder. It looks like typical hydraulic steering with no mechanical backup. There may be some sort of stop collar near the top of the rudder posts that would prevent the post dropping out of the bottom. But the packing box is so corroded that it could totally fail. Even if the rudder is contained in the event of a packing box failure if it jams one rudder then both are inoperative.

If your surveyor won't give an assessment of the potential and risk of failure consider working with one of the yard's senior mechanical techs.

 

[AquaAura]

It's bronze you can see it in my original photo also it looks like the example on the right the one with the backing plate. It is supported by the large stainless stand on the inside so it is supported in two places.

Surveyor just said it needs to be cleaned and repacked.

 

[mvweebles]

Surveyor just said it needs to be cleaned and repacked.

Thats good - he's there and with experience so you have to go with his experience. If he says there's good metal, great.

But I have a question - I added a few arrows to your original picture. I have not seen bronze oxidize like this which was cause for my alarm. The corners of the plate seem wasted too. Maybe I'm just not seeing this correctly. Any ideas what is showing?

Peter

 

[AquaAura]

I believe what looks to be corroded and flaking is black sealant not the metal. Unfortunately I am not close to this boat and I should have scrubbed and cleaned these when I was there to inspect further. The owner lives very close so I am going to have him do this and take photos for further investigation to see how bad it is.

 

[rslifkin]

Cleaning it up will definitely give a much better idea of what's going on. It's hard to tell for sure what's sealant, what's corrosion, and what's dirt or salt residue added to the mix.

 

[Comodave]

That type of shaft log is easy to repack, assuming you can get it apart, basically loosen and remove the nuts. Then take the top plate off. Use a packing removal tool, looks like a corkscrew, to pull the old packing. Find out what size packing you need. Easy way is to use drill bits and see what size drill bit fits in between the shaft and the side of the log. Cut the new packing by looping it around the rudder shaft and cutting it with a razor blade. Then insert the new packing down into the cavity. I use a piece of PVC that has the same ID as the rudder shaft OD and cut it in two lengthwise. Then wrap the new packing around the rudder shaft and push it in with the PVC. That way it will slide in evenly. Then add more wraps to fill the cavity. Turn the cuts so they are staggered so water can’t just run up through the cuts. I like Duramax packing.

As to the condition of the shaft log. I would take an awl and poke it to see if it is solid or is it corroded away. Maybe get a brass or bronze brush and clean off some of the crap so you can see it clearly. Then make a decision as to keep it or replace it.

 

[Gdavid]

Gdavid- you always have a decent handle on stuff like this. What do you think the chances of crevice corrosion to the rudder post as Portage Bay experienced?

Peter

That is kind of you to say, I hesitate to guess but, if pressed I would guess 50%. It isn't spinning like prop shaft so the sealing surface wouldn't be as concerning to me as the possibility of being weakened and breaking the rudder shaft, as it is spade style and unsupported.

You asked for opinions. Mine is this is potentially very serious and not worth taking any chances.

Before you decide to cruise farther than the soonest possible haul out, you did say she's back in the water? Consider the likely and possible failures. Think how you will handle said failures. I see the possibility for loss of steering and or serious flooding. But that's just me looking at a few pics.

What I see is twin rudders tied together with the steering ram attached to one rudder. It looks like typical hydraulic steering with no mechanical backup. There may be some sort of stop collar near the top of the rudder posts that would prevent the post dropping out of the bottom. But the packing box is so corroded that it could totally fail. Even if the rudder is contained in the event of a packing box failure if it jams one rudder then both are inoperative.

If your surveyor won't give an assessment of the potential and risk of failure consider working with one of the yard's senior mechanical techs.

As the boat is currently out of the water, it seems like a no -brainer to pull it apart, clean it up, re-bed it to the hull and repack it. A significant cost of this job would be the haul and launch expense. I am not as optimistic as the surveyor, but if waiting a week for a new fitting is the worst case scenario of taking on the repair now, that doesn't seem bad at all.

Taking care of your things that could sink your boat is just good seamanship in my opinion, knock it out as soon as the the boat is settled on and sleep better at night.

 

[Comodave]

He said the boat was just out for the survey and is back in the water.

 

[BruceK]

Before my boat was delivered Melbourne>Sydney 600 miles a leaking rudder shaft was serviced. When worked on in Sydney the rudder tube was found damaged and required removal and repair, a substantial job, prime cause a flexing steering rack. Until you get into it you can`t know what`s involved. I understand reluctance to ask the owner to fix things but if you can inspect the work or get someone else to, it might make sense to proceed that way.

 

[AquaAura]

I am going to look at it further tomorrow. This steering system seems to be built better than others I have seen since it has the stainless tower above the stuffing box for additional support rather than coming thru the hull then directly to the steering shaft. There is no movement from below or above as I did at least check that.

 

[AquaAura]

Made it back to the boat yesterday and scraped and cleaned off the boxes. They are completely solid with zero issues. That photo I took made them look horrible but they look nothing like that. Crisis averted ��

 

[Comodave]

Glad to hear that. If they are dripping you probably will want to repack them but at your leisure.

 

[PM]

Both sides should be replaced. It could get expensive. Probably $350 per side for parts and at least one boating unit ($1,000) per side for labor. Plan on three boating units for the job ($3,000).

On the bright side, the seller should deduct this cost from the selling price.

No, it is not urgent. Wait until the boat comes out in the fall.

pete

 

[JosieWhales]

What's the opinion on backing plates?
We are looking to service our twin rudders also. The existing plates are pressure treated plywood and we are thinking of replacing with fiberglass board epoxyed to interior hull. Than proper sealant. Thanks for any info.

 

[rslifkin]

What's the opinion on backing plates?
We are looking to service our twin rudders also. The existing plates are pressure treated plywood and we are thinking of replacing with fiberglass board epoxyed to interior hull. Than proper sealant. Thanks for any info.

Your plan is a good one. G10 or other similar fiberglass board bedded to the hull with thickened epoxy makes an excellent backing plate.