Saturday, November 27, 2021

Protect your P bracket!

This may be an unusual problem as I have not found other owners who have experienced it, perhaps they have been lucky, but Sancerre's bronze P bracket was rotting from galvanic action to the extent that small pieces could easily be removed with a screw driver. Fortunately the damage was limited to the front of the lower "hub" section, its structural integrity was not affected and after grinding the degraded material away the cutlass bearing could be refitted with no play in it.

One of the pair of P-Bracket anodes after just one
year before I fitted a galvanic isolator. Those on
the shaft were also heavily eroded.
The likely cause was dodgy marina shore power connections (if the marina has not got properly earthed connections your anodes can be eroded by any boat in the area as well as your own), this would not have been helped by the the P bracket not being bonded to the engine. The later can't easily be fixed so after finding the problem I put a small disk anode on each side of the bracket, after just one year this was severely eroded but did its job protecting the bronze, so that is the quick and fairly cheap fix.

For 2021 I installed a galvanic isolator in the mains power system, always a good idea but not something I had got round to doing, I also renewed the "P" bracket anode and to be on the safe side I replaced the wiring for the bilge pump which had a set of connecters that could have rested in bilge water. 

Hopefully the problem is now sorted, I shall find out when I get to check the anodes when the boat is lifted but when I dived on the boat in August all of the anodes looked to be in far better shape than I would have expected in previous years.

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