Need some help on Skeg issue

We are working on the bottom of our new boat and came across this issue of rusting on the skeg.


Is this serious and how do we repair.
Thanks for your time.

Use a magnet to be sure that is iron or steel.
After that I would sand to bare metal and see what's going on.

This looks like the "tongue" supporting the rudder lower bearing was welded onto the skeg. Use a needle gun and grinder to clean off the rust scale. It's not fun, might be best to hire the local yard gang to do the work, especially if you don't already own the tools. Have a look and see if you can spot any apparent failure of the weld. If no visible separation, cracks or deep pitting then decide how much deeper you want to inspect. You could hire a metals specialist to do some testing to tell you the state of the weld.

If repairs are required welding it back up is not a huge deal but best to hire an experience professional. Weld repair or no you will want to recoat with good paints designed for steel and bottom paint. There are lots of options let your boat yard painters be the guide.

All in all it's a messy job best handled by those with the tools and experience. But it's not by any means a major job. I ran a heavy steel boat most of my career that the most cost effective way to get the lower rudder bearing out and rudder down was to cut and re-weld the tongue.

I think it *could* be a problem. The skeg as you call it really looks to me like the back part of a keel but without a wider shot can't see for sure. If rusty water is dripping out, then water is getting in and "something" is rusting. This could be a small easily corrected problem or much worse than that depending on what is rusting and how much water is in there. It definitely merits thorough investigation.



Ken

A photo of the complete area would be helpful along with a photo of the rudder support inside the lazarette. Could be the skeg was assembled in sections and that section has cracked at the joint? I would take a random orbital sander and sand off any scale and paint. If there is a crack I would dremel it out. If it's just fiberglass, simple repair. If you hit metal, then more investgation will be needed to determine extent of corrosion and needed repairs.

You might have some iron objects in the bilge or lazarette and the rust is finding it's way out through the crack. Or it is something cast into the glass. Dremel should help narrow it down.

Will have a look in the lazarette.
Here’s another photo....This was filled with some type of compound which we took off...the rust is dripping and appears to be coming from the metal.
Thank you.

If it were me I would want to get a look at what’s beneath all that fairing compound. From the looks of the rust puddle on the ground it appears to be water inside the keel leaking out. The source of the rust is probably internal and it’s emergence seems to be occurring where the fiberglass laminate structure has been compromised. From the first photo it appears your shoe is made of fiberglass and not metal.

Looks kinda like mine but a bit worse.

Can anyone verify it is rusty water? Maybe a powerful magnet could determine if there is any steel around...not sure at what point rusty iron is too weak to detect.

Mine often looks more like the brown water from saturated teak. Cracks that develop all the way from the bilge, hollow keel and shaft log could be transporting water of that color. There could also be a teak buried back towards the shoe

The trick is if the cracks allowing the water to migrate back that far are structural or not. On my boat, serious pushing on the show does not seem to affect my cracks yet. My keel has a seem that runs the full length of it as if the hull was laid up in 2 halves which isn't out of the question.

JudyP said:

We are working on the bottom of our new boat and came across this issue of rusting on the skeg.

Click to expand...

Just sayin'

There is most likely a strip of metal extending from the lower bearing, along the middle of the skeg, extending to some point past the stern tube. The lower rudder bearing needs support and it would not be solely fiberglass.

It would appear that the skeg may have hit bottom at some point and cracked. The rust appears to be combination of a leak from the bilge and corrosion from the lower bearing support bar.

In any case, it's time for excavation to expose the support bar and completely grind out any cracks. Clean up any steel corrosion, then reglass. If the support bar is severely corroded you could just weld another bar to bridge the bad spot. I don't see this turning into a huge project but it should definitely be repaired.

Maybe, maybe not metal in there.



Shamrock keel drives that were all glass...I know I cut them off on a couple. They had a prop strut, not the rudder, that attached to the skeg with no metal in it. I don't believe mine does either. No evidence of it...just a metal cup the rudder sits in.



But either way a little digging and or crack investigation is worthwhile.

fstbttms said:

Just sayin'

Click to expand...

Skeg where I come from....


Wikipedia - "A skeg, (skegg or skag) is a sternward extension of the keel of boats and ships which have a rudder mounted on the centre line."


I think weed shoe is cool too.... especially around kelp I would hope...

Water still dripping indicates it is inside somewhere. As earlier sand it down and see what you find. Too early to talk about fixed until you know what's going on.

Well just waiting now till the warmer weather will get at this with a grinder and dremel to see what is happening....
Again good info as usual.

Yes I agree I cannot tell from the picture if it's rust or brown water from wet rotted wood.
Mine sort of looked like that. I had to drill and thread a hole for a plug so the water could drain out. Then I was able to fix the fiberglass.
Water got into the keel from the bilge. 2 screws holding bilge pumps penetrated the fiberglass in the bilge and that's how the water got it. It was an easy fix once I figured out where the breech was.
Good luck.