Rudder Shaft and Bushings
The P26 has an aluminum rudder shaft that is subject to wear and corrosion. There have been failures and losses of the rudder at sea. A couple of shops have replacement rudders. More details can be found on this page:
dan.pfeiffer.net/p26/

Cockpit Sole Delamination
The cockpit sole is balsa cored and water can get in when the OEM silicone sealant at the top of the rudder tube fails. More details can be found on this page:
dan.pfeiffer.net/p26/

Mast Step and Support Beam
The P26 mast us deck stepped and supported by two compression posts and a plywood beam that spans the door to the head compartment. The deck is plywood cored under the mast step. When the seal at the mast step fails water can get into the deck core and into the support beam causing delamination. This can lead to a depression in the declk around the mast step where water can collect (causing more dammage).

Compression Post Base in Bilge (early models)
Earlier P26's had the mast comrpression posts extending down into the bilge. This can lead to water dammage as the posts wick water from the bilge (if it's wet).

Cast Iron Keel
The P26 keel is cast iron. It can be a maintenance headache if not properly attended to and sealed. But it can be sealed to minimize maintenance. dan.pfeiffer.net/p26/keel.htm

Un-Stepping Mast
Unstepping mast with improvised crane