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Captainraw 07-11-2012 20:42

Rust on keel step...
Hello, I am considering buying a '66 Morgan 34 and was wondering if anyone knows how to address rust/corrosion on a keel step. I don't want this to be a deal-breaker, but would like to found out if there are some good solutions out there to address this issue.

skipmac 07-11-2012 20:59

Re: Rust on keel step...
I assume you are talking about a mast stepped on the keel and the step where the base of the mast sits is rusted?

If yes, I would replace it. An aluminum mast in a rusty steel step in the bilge will create a galvanic reaction between the aluminum and iron and the end of the mast will corrode away. I know because that's what happened to the mast in my boat and is a common problem with a lot of Pearons.

Did it myself so wasn't a lot of dollars out of pocket. I had to cut 3" of corroded metal off the bottom of the mast. The tossed the old step and replaced it with one I made myself out of UHMWPE and aluminum. Made ti 3" taller to make up for the piece cut off the mast. Whole thing took a few hours and cost about $300 plus the cost to pull the mast which I was going to do anyway.

Captainraw 08-11-2012 14:51

Re: Rust on keel step...
Thanks for the reply Skipmac. I'm not sure how different the Morgan set-up is compared to your Pearson, but when I removed the access panel in the cabin sole (it houses the swing keel box, cables and bilge) to try and get a better look at the step, I could see quite a bit of corrosion and flaking at the step. This compartment only gives a partial view of the step, the rest being obscured by the teak cabin sole. I assume I would have to remove that area of the sole to properly rebuild the step, which seems more problematic but not impossible (I hope!).
This would be my first big boat and I have to admit that the idea of doing it myself is daunting. I guess it would be hard to say what it could cost me to have it done by a professional...
The owner of the boat has taken good care of her for the most part, and is only the second owner in 46 years. He has offered me what I think is a very good price, but I am trying to get a handle on what it may cost me to get her up to snuff. She's a great sailing boat and perfect for the Chesapeake where we live.
I appreciated your reply and any other tips/suggestions you may have.

zeehag 08-11-2012 15:41

Re: Rust on keel step...
1966 morgan is a good boat--the rust shouldnt be a deal breaker--good luck and have fun!

Nicholson58 08-11-2012 15:46

Re: Rust on keel step...
If you do a search on replacing or rebuilding a mast step you will probably find a few photo-essays. Probably a few right here.

skipmac 08-11-2012 17:48

Re: Rust on keel step...
Hi Rob,

Sorry but I'm still sure I am clear on what you're describing so if you don't mind, let me ask a couple of questions.

Does the mast go through the deck, through the cabin sole and down into the bilge area?

If yes to the first question, is the bottom of the mast sitting on that rusty part you are seeing?

If the mast is not sitting on the rusted part, can you describe its function or what is attached to it or some other description?

If you could post photos that would help a lot, the cabin sole, the access panel and if you can hold the camera in the bilge and point it towards the rusted part even better.

By the way, I think the '66 Morgan 34 is a centerboard and not a swing keel.

From what I can tell from your descrtiption I would not call this a deal breaker but you do need to figure out what's going on there.

Captainraw 08-11-2012 19:16

Re: Rust on keel step...
Hi Skipmac, thanks for your prompt reply. Yes, the mast goes thru the deck and sole and seems to rest on the step @ 2" below the sole. From what I can see, it doesn't technically go into the bilge, though if the bilge water level rises far enough there is water in this area; not the norm.
Yes to your question of the mast step sitting on this rusty area. All I can see from the the cabin sole access panel is the aft section of the keel step, the rest of it (75%?) is under the original teak cabin sole. There are quite a bit of rusty flakes and corrosion apparent from that one angle.
Perhaps I am getting my sailing vernacular mixed up, but when I helped commission the boat this past Spring, when I lowered the CB it came down from aft to fwd; does'nt that make it a swing vs CB? Please correct me if I'm wrong.
I'm heading to the boat tomorrow and will take some pix. I am new to this forum as a member, but I assume it's straight forward to upload pix?
I am of course having a marine survey done before I make my final decision, and he is going to see the boat come out of the water and check for moisture content in the hull, blisters, etc. The present Westebeke engine (33hp) was installed @ mid '80's, rebuilt in 2000 and had 1200 hrs at the time; it now has @ 2200 hrs. Didn't sail her alot this season, but she burned only @ 2 qts the whole season. Is there an hour rule of thumb for deisel engines as far as longevity do you know?
Thanks again for your input/comments Skipmac. Where do you sail by the way?

roverhi 08-11-2012 20:12

Re: Rust on keel step...
The center board on a Morgan pivots from the forward end, not the aft. If it did indeed pivot from aft, the C/B axle or the board itself is broken and the aft end is jammed in the C/B trunk. Be very careful because you will lose the board if the lift cable breaks.

A swing keel is a ballasted retractable keel. Usually it is the only ballast in the boat. Not fond of swing keels because they can retract in a hard knockdown making the boat stable when inverted. Otherwise the boat will just roll over and stay upside down. Center board boats are ballasted in the hull either with a bolted on ballast keel that houses the board or with internal balast that board fits into. The Morgan had an internal cast lead keel.

The best way to evaluate the keel step is to pull the mast. Some boats, like the Cal 40, had steel mast steps that are prone to rusting. Not sure if that is the case with the M34. Very common for boats with keel stepped masts that have had standing water around the step to have the aluminum mast corrode away. Common fix is to cut off the corroded section and build up the step to keep the original mast length. Other solution is to just shorten the mast and all the rigging.

Have always liked the looks of Charlie Morgan's boats. Sailed against a couple of M34s in the early days of the IOR rule. They couldn't point as high as the Chance 30-30 I raced on but ran away from us on a reach. We had to hope the course would let us put up a spinnaker if we were to have a chance off the wind.

Here is some info. and line drawings of the Morgan 34:
MORGAN 34 sailboat specifications and details on

skipmac 08-11-2012 20:15

Re: Rust on keel step...
Hi Rob,

OK, I am clear now. This does sound like the rusty part you see is the mast step, which is the what holds the bottom of the mast. It is common for the mast step to not sit right down on the bilge but to sit on top of a pedestal built up in the bilge to keep the area out of water that may collect in the bilge. However even if the step isn't covered with water over time it will stay damp and rust. The concern here, especially if the step is rusty and considering the age of the boat, is more the reaction between the two different metals, the iron in the step and the aluminum in the mast.

What happens is the Al and Fe make an electrical circuit and the Al in the mast is eaten away. It may be just minor and cosmetic or it could be structural. Considering the age of the boat and the years it has had to react I think this area must be examined.

The good news is the problem is almost certainly just where the two metals touch so the rest of the mast should be fine.

From your description it sounds like it will be difficult to inspect this area if it is under the cabin sole and there is no area that lifts up to give access. Whatever it takes you do need to inspect this. On my boat, a 1984 I had the exact same situation and the bottom three inches of my mast were completely eaten away. I can't believe the mast had not dropped three inches down into the step.

This should not be a really difficult fix if you do have the corrosion. Worst case cut off the bad part of the mast and either deal with a 2-3" shorter mast or build up the pedestal a little higher to compensate. Long term I would get rid of the steel mast step and replace it with aluminum or a composite. You could probably get away with sanding, painting and adding something to insulate the mast from the step. That's a band aid solution but would probably get you by for years.

Regarding the keel vs centerboard. Either would have a pivot in front allowing the back end to go up and down. The difference is in size and weight. A swing keel it larger, heavier and is a ballast component for the boat's stability where a centerboard is mainly is to add lift and improve upwind performance. The centerboard could still be made of bronze or steel and be somewhat heavy but not many hundreds of pounds that an actual swing keel would weigh even on a small boat.

Unfortunately at the moment I don't sail anywhere. I bought a fixer upper and have spend the last three years fixing her up. Getting close to the end and hope to be in the water this winter. Boat is just outside of Gainesville FL. The lat/lon is in my signature line if you want to find it on a map.

zeehag 09-11-2012 04:34

Re: Rust on keel step...
can you post pix of the trouble spot?? then we will be able to be more intelligent with answering your question. thankyou.

Nicholson58 10-11-2012 08:50

Re: Rust on keel step...
6 Attachment(s)
The Morgan 34 section looks like the mast rests very close to the inside hull surface. I raced a Morgan 38 Heritage One-Ton of about 70's vintage. The mast rested in a step that was part of a large armature weldment. It consisted of all steel flat stock on edge and welded into a frame that was glassed into the hull. Pert and starbord sides were formed up the insides of the lockers and was about 12 feet long. THe lockers were structural and the steel was bolted to them as well as the bulkheads. It was below the entire cabin floor. The mast step was central to this weldment. We kept the metal well painted and dry.

The keel shown at the link looks like ours on our Camper & Nicholson. The hinge pin is forward so the keel end drops from the aft end. This is normal as running aground will lift the keel. Our semi-full keel is lead ballasted and the swing CB is not a significant part of the whole. We had to replace the original CB because the original bronze and FRP fin was cracked and bent near the pivot. The new board is all FRP with a 360 # lead tip. The old board was 1700# total and was only a small percentage of our total ballast. (55,000# disp and 16 beam) If I compare that to the total of fuel and water tanks full/empty is 7000 #. There were two CB's offered as well. The first 6 buiilt has a solid bronze board weighing 7000# and a "light weight" cored board 1200#. The light board was badly designed and cracked.

In the photos you can see the swing pin central to the keel. There were two configurations sold at the time. One with CB and one with deeper fixed keel. The cast lead is forward of the CB.

If you loose your lift pennant and the board falls you will be diving to install a new one. If it happens in shallow water you will be well anchored. On the hard or in the lift sling you may want to slack and drop the board to inspect. Make sure you inspect the sheaves and bearings. Edges of sheaves can become very sharp and loss of a bearing will drop the pennant.

Captainraw 10-11-2012 09:08

Re: Rust on keel step...
Thanks for the follow-up. I understand everything you're telling me and am encouraged that it is a fixable item. I took some pictures to post but, even when shining a flashlight, they don't show the area very well. I know from what I can see though that it needs to be addressed and I'm going to unstep the mast when I haul the boat next week. In conversations with the surveyor and yard owner, they both agree that it something that can be repaired; the question is whether I am capable of doing it myself. I would definately choose the aluminum/composite option. Cutting into the sole to have proper access is unfortunate but neccessary I'm guessing.
Thanks for the clarification regarding CB vs Swing; I didn't remember properly that it has a CB, and hope to give it a good inspection when we haul out by lowering it and checking the swage fitting and cable attach point.
My other reason for unstepping the mast is to check the standing rigging and replace all the exterior lighting, as none of it works. The present owner is unsure of the age of rigging, making it possibly 46 yrs old. The survey is not complete yet on the boat, but he thinks it looks OK and I just may need to replace the fittings. It strikes me that that is very old for rigging and should be replaced. Any opinion?
Thanks again for your input. Good luck with the final stages of your overhaul and I hope you get in the water soon.

Captainraw 10-11-2012 09:18

Re: Rust on keel step...
Thanks for your response and clarification. You are right of course, it has a CB that pivots from the fwd end. I am going to pull the mast when I haul it next week and almost suredly will have to repair it in some fashion as you describe.

Captainraw 10-11-2012 09:21

Re: Rust on keel step...
Nicholson58, thanks for your reply and the tip about checking the sheaves/bearings. Pretty sure they are original, so will need to look closely.

roverhi 10-11-2012 09:34

Re: Rust on keel step...
I would pull the chainplates and inspect if they are more than 10 years old or do it anyway just in case. It's a relatively easy thing to do on most boats. If the chainplates are fiberglass encased, it's a more involved job but absolutely necessary to do. SS embedded in fiberglass is a perfect set up for crevice corrosion. SS rigging in the tropics is generally given a 10 years lifespan. It can go much longer with careful inspection and replacement when necessary. I do all my own rigging with Norseman terminals. It's simple and relatively inexpnsive to do your own rigging with mechanical terminals.

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