Rusted comp post on '82 Hunter 30

[malyea]

I have a deposit on an '82 Hunter 30 in good shape.

I haven't yet had a formal survey as required by BoatUS for insurance, but after yesterdays $120, 2 hour inspection, I like the boat, want to close the deal and take ownership - but I want to know what repairs I'm in for.

I'm concerned about the amount of rusting that has occurred on the bottom 6-8" of the metal compression post in the bilge. It appears to be an inverted 'cross' configuration with a vertical extension downward from the cross beam into the bilge allowing the extension to be ''resting on the keel' or 'stepped to the keel' 6-8" below the metal cross member. The material appears to be a metal 2x2.

Good news: The mast step area is level and currently shows no sign of mast settling or comp post failure - thus far.

The metal comp post has 'large flakes' of flaking rust on the surface that flake off when chipped at. Chipping at the rusted metal with a flathead screwdriver returns a solid sounding 'clinck' of metal on solid metal. But there's lot's of flaking rust....

I'm trying to research and read the previous threads on this topic of rusted comp posts....

How do I determine the degree of rusting that has occurred?

How do I assess the structural integrity of the rusted base of the compression post?

How do I assess how far up the comp post the rust reaches?

How long before the rusting compromises the comp post integrity?

Can I fix it completely (ie, arrest the rusting) with steel brushing, naval jelley, rust inhibiting compounds, etc OR will that treatment just delay the inevitable r/r of the comp post?

If/when I have the comp post replaced, what is the process and how much (ballpark) is the cost, labor and materials?

Just whip out your crystal ball please......How should I proceed since I haven't yet taken ownership?

Any help/advice/links would be greatly apreciated!

Thanks, Mike

[sailingdog]

I'm surprised the surveyor didn't tell you more about the compression post. Photos would really help.

[malyea]

As per my post, I haven't yet had a survey - so no surveyor....yet. Just had an 'inspection' to see if boat warrants cost of a formal survey and I knew to check for comp post rust....and it's there....

Looking for help from anyone with actual experience in a similar situation.

Thanks

[sailingdog]

You paid $120 for an inspection??? I would recommend you read the Boat Inspection Trip Tips thread I started, as it will help you determine what problems this boat has and whether it is worth getting a survey on or not. Unless the person you paid to do the inspection gave you a report, doing your own "inspection" of the boat is probably worthwhile.

Is the post stainless steel or regular steel? From your description of the metal—having large flakes of rust, I'm guessing it isn't stainless steel. I've dealt with damaged compression posts on several boats. If the post isn't stainless steel, I would highly recommend replacing it with one that is. Wire brushing the rusted areas will often let you figure out whether it is just surface corrosion or structural corrosion. However, since you don't own the boat, doing that would require the owner's permission.

While you might prolong the life of the compression post by using OSPHO or other rust inhibiting compounds and painting it, I would suggest you find out why the compression post has rusted so badly to being with. If the boat has a normally wet bilge, then you may have other issues to deal with. A wet bilge, especially if the bilge is electrically hot, could easily result in accelerated corrosion. It would probably be wise to check any metal through-hulls and seacocks, as well as the propshaft and packing box.

As for cost estimates, that will be pretty specific to the boat, and depends on whether you need to make a new compression post step, what the post is made of, whether you do the installation or hire someone else to do it and so on. You will need to take the mast down to replace it, so if you're planning on replacing the standing rigging, this might be a good time to do so.

BTW, copping an attitude isn't going to win you any friends...

[malyea]

Great "Inspection Tips" - thanks, just doesn't address my question. I also wouldn't expect rust on stainless.....

Maybe if there's some folks out there with old Hunter experience (and not such thin skin) we can get a good and useful discussion going.

Thanks to all in advance!

[sailingdog]

If you submerse stainless steel in salt water and add electricity... you're going to get rust. Stainless steel is just that "stain less, not stain free". You still didn't answer what the compression post is made of.

[svHyLyte]

Mike--

The unfortunate fact is that sailboats invariably end up with water in the bilge at some point or other. With keel stepped masts, frequently through the mast itself. With deck-stepped masts, through all the other penetrations. Given that, it is not unlikely that the boat you are viewing had more or less water in the bilge on more than a few occassions and any minor flaw in a protective coating on steel will have allowed rust to start. Once it does it makes its way under the adjoining coating, popping that off and proceeds apace.

Fortunately, rusting steel is not so much a problem as it might appear as the volumn of "rust" one sees is roughly 5x greater than the amount of steel or iron that was "rusted". One can wire brush back to bright metal, thoroughly coat the surfaces with "Osphoe", a phosphoric acid solution that binds with oxidized steel, and then paint the damaged surfaces with a good two part or monopoxy paint, or with one of the zinc based protectant coatings.

The only question I would have is whether the bottom end of the tube is fully sealed so that moisture could not have gotten inside. If not, what you are seeing on the outside, is also going on within the tube, and that you cannot correct. Replacing a compression post may or may not be a major project, depending upon the original build. If you really like the boat, it might be wise to use google to seek out an owners association and see what other owners of the boat have experienced. In any case, if you have any misgivings at all, pass, or advise the seeler that any sale would be conditioned upon the replacement of the post.

FWIW...

[malyea]

Thanks HyLyte.

Limited online research at Hunter.org thus far indicates the metal in question is iron.

[svHyLyte]

Mike--

That might be a plus as Iron pipe is actually preferable to steel, particularly when covered with a good zinc coating. The only advantage to steel is that it is relatively stronger than iron for certain applications.

[AlanBrown]

Had the same problem with my 1981 Hunter 30. My surveyor picked it up during his inspection in 2001.

Here's what I did to solve the problem.

I made a plastic frame all around the rusty plate. I then filled the frame with a two-part epoxy until the rusty plate and the bottom of the compression post were totally encapsulated. I knew that I couldn't correct the rusting problem, but I knew the epoxy would prevent it from spreading.

Nine years and a couple bad hurricanes later, it still looks good.

The cost of replacing the compression post would be significant.

I mentioned some other problems I encountered with my Hunter in a thread last month, "Any thoughts on a 1983 Hunter 34".

Let me know if I can be of any more assistance.