Snapped Edson pedestal mounting bolt

[NewToTheRoad]

And this is how one thing leads to another..

Small leak in to back cabin which I feel is coming from the Edson Pedestal.  Looks like the previous owners attempted to fix with tape and caulk.  Anyhow, after researching some previous posts my plan was to back off on the nuts, lift up the pedestal slightly (if possible), and put some butyl tape underneath.  Until I sheared off the bolt.

Looks to me as if what's left of the aluminum bolt is corroded to the backing plate.  The entire nut came off as did the lock washer.  On their site Edson states as of 1987 they began using aluminum bolts to prevent corrosion.

I would think that I could just push the remaining up and pop the hex head out of the pedestal base.  No luck.  I can barely get a hammer in there and tapping the stub upward doesn't move it.  Could the bolt be corroded to the base throughout?

If I can't get it to move, is my only option to drill out the hex aluminum bolt from above?  Maybe a right angle drill from below????

Hard to tell from the attached pic but the back left is the one I mugged up..

Thanks,
Bryan

[Noah]

Before drilling, I would try soaking for a few days with Kroil or some other penetrating oil and then try an impact driver. There is a chance this MAY work.

[KWKloeber]

Bryan

It's difficult to figure out what exactly will work not having hands-on but if soaking doesn't do what you need, I think I would definitely work from above. Why fight it with the cramped space?  Although, I have had many a time someone told me "I can't move it, I'll have to cut it or torch it off" and with enough love and persuasion I've been able to move it.

Obviously the idea is not to get into or damage the base, so I'd start out with a 1/8 bit in the exact center. Successively larger until I had enough of a hole to work in.  The idea would be to get it large enough that I could slip a narrow blade down to cut a slot out to the bolt OD. Then work with a punch or drift pin to try and collapse the "shell." Maybe three slots?

  Possibly when soaking, you'll find that the leak was down through the bolt head and that's what's corroded it to the base??  That's a good case for using Noalox on aluminum 
fasteners. 

kk

[NewToTheRoad]

Not sure how easily I can soak as it broke off pretty flush to the mounting bracket with no thread exposed.  It almost feels like the bolt was threaded into the bracket, but that can't be the case as these bolts were designed by Edson to be tightened by one person, below deck.  Or should I say designed to be snapped off by said person..

I'm attaching a pic that I pulled off the web (not my boat) showing how the hex heads are recessed in hex shaped holes to allow the tightening from below.  Mine has no rust on the base whatsoever though.  You could never get a wrench or socket around that from above.  Maybe if water was getting in (doubtful) from the bolts then I can get some oil in from the top.

I will try and bang from below a bit more to see if I can dislodge it.

[KWKloeber]

Also use a heavy punch, hardened bolt or etc and wrap sharply on the head, spraying w/ blaster. You want to break the connection and get the microscopic corrosion attacker to draw into any crevice you can by capillary action. Pin point heat right on the head (pencil flame) would assist to break the bond.

kk

[Noah]

I still recommend "soaking" from the top, then hitting with a drift from the bottom, before drilling.

[J_Sail]

I agree with soaking from the top, but if it was mine, I would bang on it from the top as well - and bang on it a lot! Each time you hit it, you are creating compression vibrations that will hopefully allow tiny amounts of the penetrating oil (your pick of brands) to find their way around the head and down the bolt to where it's needed. Use whatever technique lets you hit the head hard and transfer the energy without damaging anything else.

Nothing wrong with working from both ends, but I would start where it's easiest.

[Noah]

You might consider removing your compass before wailing on the pedestal?? May not be an issue but...

[britinusa]

Any chance you can get a dremel in from below and cut off the nuts? or am I missing the point?

cut off the nuts and knock out from below with one of those fancy cordless Hammers (Ball pein ) 

Paul

[NewToTheRoad]

Paul,
  Who needs a dremel when a socket wrench shears them off.    I wasn't trying to shears them just remove them.  Good idea on the ball pein.  Maybe I can get me one along with some Blast.  Will let you know.
Bryan

[Jim Hardesty]

Bryan,
I'm thinking the bolt is being held in by the sealer.  If you agree, try digging out what you can around the bolt then maybe a bit of acetone or a product called "Release" I think.  Be careful don't want to have to reseal the entire pedestal.  Another thought is to drill from the top and thread it with a tap, put in a screw and try to lift it with a crow bar, think pulling a nail.  Steady pressure may work better than hammer persuasion.
Just my thoughts, hope it comes right out.
Jim

[NewToTheRoad]

Thanks Jim.

Boat splashed before I could fix it and I'm on a mooring, so I may just need to put this off for a while.  What I don't want to do is to create a bigger problem for myself while on a mooring.  My guess is that with the bolt frozen in place it's just as good as if the nut were still on.  And, i don't plan on crossing any oceans soon.

I will update this post with what I do and how it came out.

Bryan