Deck Fill Plates

When we did our first inspection of Circe, 2 years ago, we noticed that three of the four deck fill fittings needed help. The fuel fill plate was in good shape but the two water fill plates were only marginal and the waste pump-out fitting was really gnarly looking. The fuel fitting was a newer cast stainless design with a stainless cap but all the rest were the original (Perko) cast ZAMAK units. The water fills had FRP caps and the waste fitting had a ZAMAK cap. 

Because we have had so many other projects to occupy us we let the replacement of the deck plates slide down 'The List'.....until now. We recently saw some cast stainless steel deck plate fittings (Sea Dog) on sale at a local chandlery so we decided to jump in and replace the three older fittings. That was our first mistake!

Here is a shot of the Waste Pump-Out, the worst of the three fittings we decided to replace. Both the body and the cap are corroded and the sealing surface for the pump-out nozzle was badly pitted, making pump-outs a challenge at times. 

This shot shows one of the two water fittings, they were both in the same condition. There was very little corrosion on the body of either fitting but the threads on both caps were shot and the cap tethers were missing. Also the O ring sealing surfaces for the caps were pitted.

Here is a close up of what was left of the threads on one of the FRP water fill caps.

Another close up of the corroded internal threads and pitted sealing face.

Here is the all-stainless Sea Dog fitting, more rugged and durable than the Perko unit and with a much better price. 

We were so excited to get some more durable parts that we quickly checked the overall flange and hose sizes on the old fittings (our second mistake!) and went to pick up some Sea Dog replacements. They looked great, even with a slightly smaller flange diameter, but we thought we could make them work.....our third mistake! We had been so anxious to kiss the old Perko units goodbye, we neglected to check the body diameter of the fittings......Duh! 

As soon as we pulled the first of the old fittings we saw that the bodies were 2 3/4" dia. with a hole in the deck to suit. The bodies of the new Sea Dog fittings were only 2 3/8" dia. so their mounting screws would be sitting in fresh air....! No way could we make them work.

We spent several hours researching other alternatives but eventually realised that, because of the size of the holes in the deck, we would have to get more Perkos! Short of filling and re-cutting all the deck holes we couldn't use any of the all-stainless fittings we had bought. Back to the chandlery to swap the fittings and pay a chunk more money!

Here is one of the new Perko's. We can't understand why a ZAMAK cast fitting with a plastic cap is so much more expensive than a cast and machined solid stainless one?

The through-deck holes for the Perko fittings are huge, much bigger than the hole needed for any of the competitive products, Scandvik, Whitecap, etc! Evidently, once you have a Perko fitting there is no going back, without major deck modification.

We used butyl mastic to seal the replacement fittings. It is so much nicer to work with than any of the caulks we have tried.

Here is the finished installation of the waste fitting. Nice enough looking and easy to replace on a like-for-like basis, but the price!!!!!......and those FRP caps are just really cheesy!