'79 Hunter 30 mast subsiding into deck

[debbinkt]

The mast on my 1979 H30 is subsiding into the deck. This is because the iron I-beam that was originally installed in the bilge to support the compression post is rusting away and losing its shape. Thus, the compression post is dropping. The mast has slumped about 3/16 of an inch into the deck. Interestingly the deck has not cracked, it has just become depressed around the base of the mast.

Has anyone dealt with this before?

 

[jdhohmann]

I know a few models have a wood compression post behind the facade in the cabin, and it usually starts to rot and compress. You might want to look into that first for verification

 

[kito]

I bought my 79 H30 with the mast already down. The steel I-beam was rusted to the point only the top flange was left. It's a bad design imo to have a steel support like that sitting in the bilge. I need to install my new support still. I made my own out of 2 6" structural aluminum channels bolted together. The bottom section will be completely imbedded in resin.

 

[debbinkt]

jacking up the compression post?

I bought my 79 H30 with the mast already down. The steel I-beam was rusted to the point only the top flange was left. It's a bad design imo to have a steel support like that sitting in the bilge. I need to install my new support still. I made my own out of 2 6" structural aluminum channels bolted together. The bottom section will be completely imbedded in resin.

Thanks for the information. How did you push the compression post, and along with it the deck and the mast step, back intro position before installing the new support?

 

[kito]

What I plan on doing is to cut 1/4" thick 6"x6" aluminum plates that will lay in layers on top of the aluminum channel. The last plate will have to be driven in with a heavy hammer. I will then drill a couple holes through the plates and channel and bolt it together so the plates will not move. Not sure if that is necessary though. My mast is down and I don't see any sag on the deck on mine. You may need to take your teak plate off to access the compression post and rig something up to get a bottle jack to raise it up.