Rudder Post Leak Help

Picture attached of my rudder post. It is weeping/leaking a small amount of water. 1984 Mainship 34. Is there a rubber O ring seal or is it packing as in the cutlass bearing? My first option here is just to tighten up the seal. I assume I would hold back on A and unscrew B, then tighten down on A and reset B. Is this the procedure recommended? Click on the picture for full size.
Thanks in advance...

Just packing nip it up and see how it goes and wait till you next lift the boat to repack.

Id be more interested in that rusty nut on the right of the photo I don't like the looks of it . Further investigation may be needed .

gaston said:

Id be more interested in that rusty nut on the right of the photo I don't like the looks of it . Further investigation may be needed .

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thanks for your reply, but at this point the leak does not seem to be originating from that nut, but from the top of the rudder post nut. I do have a philosophy that "if it ain't broke, don't fix it"..... and I have NO doubt that if I start monkeying around with that rusted nut, I will shortly have a much bigger problem.

KenM said:

Picture attached of my rudder post. It is weeping/leaking a small amount of water. 1984 Mainship 34. Is there a rubber O ring seal or is it packing as in the cutlass bearing? My first option here is just to tighten up the seal. I assume I would hold back on A and unscrew B, then tighten down on A and reset B. Is this the procedure recommended? Click on the picture for full size.
Thanks in advance...

Click to expand...

No! Well, sort of. Depends what you mean. Nut B is jamming the part nut A is part of. Turn nut B clockwise, viewed from above, to move it closer to the hull. Doubt you need to hold nut A to do this but you may. Once B is a turn or so away from it's jamming position, turn nut A clockwise, as viewed from above, to move it down the shaft, towards the hull. Likely will need no more than 1/4 turn, okay 3/8. Hold nut A and set nut B back tightly to jam it again.

KenM said:

I do have a philosophy that "if it ain't broke, don't fix it".....

Click to expand...

Hum yes not broken no need to fix it, except that if this nut break causes a major failure on your rudder while under way you will be in deep ****... just think about it...

L.

If you tighten it too much your steering will get stiffer.

Ken just a little tip. don't attempt to undo that rusted nut there's a very good chance you will snap the stud. If it was me I would cut the nut in 1/2 with a Dremal and replace it now while you have time on you side .

The first think you need to do is wire brush the assembly & soak the whole thing with PB Blaster or something similar to free up the jam nut & packing gland. From the looks of it, it doesn't look like it's going to readily turn. I would leave the rusty nut alone while the boat is in the water. It looks like it was added for a bonding wire or something. It's not securing the rudder stuffing box assembly to the hull; the one under it is. If you start fiddling with it & you happen to turn the whole bolt because there's nobody on the outside holding it , then the seal is broken & you WILL have a mess to contend with. Wait ntil you haul the boat to address the nut.

I just went thru this exact exercise with the same boat. Mine looked very similar with the exception of condition of the 1/2" nuts. The lock nut and packing gland will come apart easily. To see what you are working with you need to remove the steering arm and the board the ram mounts to, not to hard to do, the shoe will hold the rudder up. In my case the caulk between the packing gland (it is installed from the outside of the hull) and the hull was hardened and failing. Repacking the gland is pretty straightforward with the exception of not being able to see what you are doing. Re-bedding the packing gland to the hull is a much larger job requiring the removal of the shoe/prop guard, which thru bolts into the keel, the nuts are accessible (not easily) below the shaft.

Ya, I'm not going to touch the rusted nut on the packing gland while the boat is in the water. It does have two nuts holding it down, and the bolt itself seems, at least from what I can see, O.K. As an aside, while giving myself some time to investigate this, I sprayed some silicone lubricant over the upper nut that holds the rudder shaft and the weeping has diminished noticeably, at least while in the slip. Will keep an eye on it while underway to ascertain the situation. Will get some PB blaster and soak the whole magilia before attempting any adjustments.

Please note: what looks like a flange with the 4 nuts on it is really a backing plate. The packing gland is installed from outside of the hull.

Had the same problem last month on my 34MT. Turned out the whole thing had to be rebuild. $3400. - ouch !

if the leak is minimal and you are comfortable, I would leave well enough alone. Its not gonna hurt and the alternative is you crack or break something necessitating an emergency haul out. Plan on removing, cleaning and reinstalling when convenient. MK1 has 4 bolt rubber box with a plywood backing block.

It’s very important to get a section view drawing of your packing nut assembly.
Then you will have a better idea on what each threaded nut is doing. One compresses the seal on a taper against the shaft and the smaller nut locks in place and keeps it from backing off when you’re underway.

The packing is up inside nut A sometimes called the gland nut. Nut B is simply a lock nut. You may try tightening as you said. A small amount of snugging may do the trick on a rudder, doesn't work for me on a shaft though.
Nothing is likely to break after you spray it liberally with WD40 and don't apply much pressure.

Thanks for all the replies. I will try soaking with PB and a wire brush and see how it goes as far as tightening up the packing gland a bit. Access is fairly good so that is not a problem. Will do this when I return to the boat this fall. My "boat checker" reports there is no water in bilge, so there is no immediate issue. It is only "weeping" but I do want to give a fix a try. Also my propeller shaft is dripping a drop every 10 seconds or so when underway. Probably give that a go also. What I DON'T want to do is break something.

Ken, Regarding your propeller shaft, a single drop every 10 seconds while underway isn't necessarily a bad thing. I've seen instances where owners have cranked down on their shaft packing gland to much ,causing the shaft to score from the heat & friction and then having to replace it. Just something to keep in mind.

The large bronze backing nut holds the packing nut from turning. You can tap backing nut with a hammer to loosen it.
I repacked mine about 10 years ago with GFO marine packing. Very much better than flax packing. Will not score your shafts.
I also did the prop shafts. GFO Packing | SG Group Div of MGP Systems Inc.

I repacked my rudder posts on land. I did not have much room to work with and I wanted to take the rudders out and examine everything. On mine, above the packing nut is a board with a hole. Rudder shaft passes thru that and there is a shaft collar that sets the height. Collar bears on a large washer which hold the rudder up.


The rusty nut should come loose ok and you could use a propane torch to heat it.
That nut looks different than the others. One source besides HDepot or Lowes for SS is West Marine which would have a 316 instead of a 308 series SS nut.

On my boat the SS holds up ok, not seen rust like that. My rudder posts use bronze bolts and nuts and washers, all from 1970 and in good condition.

Don't worry about the rusted lock nut for now.

Don't worry about your steering getting to stiff.

Heck I wouldn't even worry about the small leak if you're going to haul the boat in the near future.

But if it's an issue for you, use some acid (with the proper precautions obviously) to clean up the box and threads, break the box nuts loose and see if you can stop the leak by slightly tightening the packing nut.

If that doesn't stop the leak then decide if you can live with the leak till you haul the boat or repack it with GFO while it's in the water.

The rudder shaft looks pretty corroded, it bronze? Is that the rudder shaft that turns?

if your going to repack, clean that up well as the packing nut needs to slide up.

Don't some boats have a real long rudder shaft where the exit top is high enough above the waterline they can not leak?, where a shaft runs up inside an external pipe.

sdowney717 said:

The rudder shaft looks pretty corroded, it bronze? Is that the rudder shaft that turns?

if your going to repack, clean that up well as the packing nut needs to slide up.

Don't some boats have a real long rudder shaft where the exit top is high enough above the waterline they can not leak?, where a shaft runs up inside an external pipe.

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Indeed that is what I have. The rudder shaft in inside a pipe and exit above waterline. The is no packing on mine, the external pipe has 2 grease zerks to refill it and is full of grease.

L.

My 2003 mk III is oozing at the base plate. The sealant is probably cracking. Not enough leak for me to bother with