Siezed stanchion post

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West Coast

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My boat has alloy stanchion post bases (bolted to an alloy toe rail) with stainless steel posts. I managed to bend one post this year (berthing in a narrow space between pontoon fingers) and so need to replace it. However the post has siezed in the socket base (dissimilar metal corrosion) and is really stuck. The base has two bolts through the alloy toe rail and one through the deck. Boat is 1993 vintage.

I am wary of applying heat to break the corrosion as do not want to put heat into the GRP, and am also wary of too much mechanical action (such as a wrench) in case I distort the toe rail.

Has anyone hit this problem before? Any suggestions?
 
Hi
I had the same problem on my Beneteau. Had to remove the alloy stanchion post base as it was also damaged. Even with the stanchion mounted in a vice and the application of heat, penetrating oil and a fair bit of bad language the base would not come off. Used a small grind wheel to cut slots in the base and managed to get it apart. Sorry not a lot of help, just my experience !.
 
I had a very similar problem with spreader ends.

What worked for me was making an oil bath of diesel. After about a week, and not too much pressure, they came apart.

Diesel really seems to get to those places where you do and don't need it to.
 
Yes, take the whole bit off, soak it in penetrating oil. Lots of patience it should come of. Hopefully you can salvage the old base. Use Duralec or wrap the lower end in plastic when you put it back together.
 
Cannot take the whole thing off - there is a vertical bolt going through the base, through the horizontal flange of the toe rail and secured under the deck with a nut or threaded plate, hard to be sure as all glassed over. To do this, I would have to cut off the post as low as I dare and hopefully the head of this bolt will be accessable!

Cheers all for the helpful advice, just wish I had taken the time before now to remove the post while I still could and greased it or something, to prevent this siezure happening
 
West Coast said:
Cannot take the whole thing off - there is a vertical bolt going through the base, through the horizontal flange of the toe rail and secured under the deck with a nut or threaded plate, hard to be sure as all glassed over. To do this, I would have to cut off the post as low as I dare and hopefully the head of this bolt will be accessable!
Click to expand...

Westerly, by any chance?

I have a similar problem: someone hit me, brealing the stanchion socket, and the mounting plate is completely inaccessible. It's going to be a new, custom made socket with mouting straddling the old one. Grr.
 
No, sadler built starlight.

Having read the comments and advice, plan now is to drill out the corroded bolts securing the base to the toe rail to see if by any chance the base is not bolted through the deck and just comes free. If it does not, next stage is to cut off the bent post to give access to the head of the bolt through the deck. If the nut/plate below is glassed, it should stay captive in which case I have a chance to remove the bolt. If the bolt is also siezed, will have to gently break out the base having cut it as much as possible exposing the stem of the bolt - should then be able to remove the bolt with a wench.

Will need a new base (I understand these are still available) and post - hate to think how much this will cost.
 
hello Simon

have responded to your post elsewhere. you should be able to check under the deck to see if there is a through bolt - my boat is Bowman but I guess the way the toe rail screws are fixed will be no different and its easy to remove the access panel and check them from underneath. they arent glassed over and dont have stainless plates underneath either.

the people who have failed to seperate alloy base and stainless stanchion simply havent applied enough heat. this was something I learned maintaining an old Norton Commando and needing to replace bronze bushes in alloy chaincases. You heated the chaincase ( adelicate casting) until the bushes dropped out! You can still buy the stanchion bases anyway so go at it with blowlamp and determination and you will succeed. You are unlikely to damage the base unless you really go mad.
 
Boiling water straight from the kettle has solved dissimilar metals bonding for me before. You need to keep reboiling and pouring until it seems pointless to keep doing it... and then do it some more! With a lot of wiggling you may find it'll suddenly release.

Best feeling in the world! (Well one of 'em anyway!):D

Good luck.

Tim
 
Assumint the stanchion is not to be re-used,are you able to get a tommy bar through the shaft of the stanchion at top or bottom and use as leverage when the hot water treatment is being done. Aternatively use a cobalt drill bit to drill out the stanchion bolt.

How powerful a drill can you get hold of that will drill out the stanchion shaft if cut off; I guess at something like a 1/2" hole would allow a saw cut through the remaining 1/4" radius left and collapse the alloy shell,leaving the base. When refitting some ptfe tape around the stanchion may helpwith the disimilar metal.
 
If the nut under the deck is glassed in then sods law says it will turn with the bolt! Glassing them in doesn't lock them. When removing the toe rail on my Konsort over half of them have not locked and had to have the glass cut off inside.
 
Make a cup

You can make a cup round the joint using some suitable material. Epoxy putty would be my choice. Fill up the cup with your choice of solvent. I've seen Coca cola recommended, or diesel or pentrating oil etc.
Give the solvent time to work.
Alternatively
If you want to keep the base and change the stanchion you could try cutting off the stanchion then cutting away at the bit left over in the socket (Dremel tool perhaps). You might be able to get a small grinding wheel in. Once you have separated at one point you can lever the bits out.
 
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