Corroded stanchion bases

[wannathermal]

On my 03 49 some of the stanchion bases have fused to the stanchions because the plastic inserts have come out or broken. Does anyone have an idea how to break up the corrosion so that I can remove the stanchions and replace the plastic inserts?
Bob

[Symphony]

You need to break up the corrosion of the aluminium. Not easy, but first try boiling water and then penetrating oil. Heat on the aluminium may help, but that is best done with the base off the boat for obvious reasons. Lots of patience required and you may find it impossible to do without removing the base and stanchion from the boat.