Seat pedestal mounting

[mikesparker]

Hello! I've got a 1985 3227...she came with fixed pedestals which had what look to be original 9" round bases with 6 screws securing them into the flybridge deck. I want to switch to adjustable pedestals but the ones I got have square bases and only 4 mounting holes. Question: Is there plywood under the deck to screw into? The screws that came out of the originals were 1/4" diameter, 2" long...Can I just clean/fill the old holes and drill/screw into the deck?

Thanks!!

[SplashyLady]

I would suggest using the original bases and finding adjustable mounts that fit. I have ladder-type teak chairs with cushions on my bridge that adjust fore and aft and fit the original mounts with a nylon spacer. There is base material under the glass, but it's not a good idea to drill more holes that you need up there - makes a path for water and problems IMHO.

[tomschauer]

Were the screws you removed from the original base wood screws or machine screws? I would think they were machine screws that were most likley threaded into an aluminum backing plate under the plywood deck core.
Soooo, there is plywood under there, but I wouldn't think four 1/4" wood screws would be sufficient to hold your seats under some conditions unless your original screws were 2" wood lags screws. At 2" there must be a lot of wood there to support the pedestals.

[bud37]

Source of the post Hello! I've got a 1985 3227...she came with fixed pedestals which had what look to be original 9" round bases with 6 screws securing them into the flybridge deck. I want to switch to adjustable pedestals but the ones I got have square bases and only 4 mounting holes. Question: Is there plywood under the deck to screw into? The screws that came out of the originals were 1/4" diameter, 2" long...Can I just clean/fill the old holes and drill/screw into the deck?

Thanks!!

I agree with Tom , if the screws are machine screws, there may be an aluminium plate. Whatever you decide, consider the loading of a pedestal seat on a flybridge boat if it gets rough.......you don't want it breaking loose with you on it in bad conditions.

[mikesparker]

They were machine screws. I’m going to change the operator seat to a height adjustable...the flanking seats will be original fixed but with swivel mounts which will raise them up. Hanks for the replies!