Ring Around the Rosy

With all the jabber about water-contaminated fuel, there’s a ton of advice to be found regarding additives, filters, and at what level to keep your fuel tank during storage. While the empty-tank/full-tank debate rages on, and most of this advice is great, nobody’s talking about the simplest DIY chore you can perform to keep water out of your fuel: change the O-rings sealing the fuel fill pipes.

The O-ring for this fuel cap looks pretty good, but over time it can flatten out. Since it’s five years old, I’m installing a new one.

If you remove your fuel cap from the pipe and look above the threads, you’ll see the O-ring. This is simply a round-sectioned, rubber-band-type washer that seals the fitting, preventing rain or spray or washdown water from seeping along the threads and getting into your tank. After a few years — five at the most, the O-ring should be changed. Just pop the old one off, lightly grease up the new one and fit it in place.

Where does one get replacement O-rings? Most major deck hardware manufacturers sell them as replacement parts. You may be able to order one direct, or your dealer or chandler can order it for you.

If you’re in a jam and need one right quick, you can take your old one to a hardware or plumbing supply store and match it up for diameter with what it has in stock.

While you’re at it, change the O-rings on your deck plates as well. These are the round fittings that either screw or snap in place to provide access throughout the boat. No sense having “dry” fuel and a wet bilge, is there? Again, seek the manufacturer’s catalog for replacements. The maker’s name is likely stamped on the underside of the cap.

Deck plate O-rings get flat as well. And if yours are pry-up models, rather than screw type, there’s always some damage at the pry-up point. Change them.

Below is a list of replacement O-rings sold by Perko (www.perko.com) and available through marine dealers.

Spare Part for PERKO Figure No.
•1613 - Polymer Gas Fill for 1-1/2" Hose
•0527 - Gas Fill for 1-1/2" Hose
•1270 - Fuel & Water Fills for 1-1/2" Hose
•0528 - Fuel, Water and Unmarked Fills for Pipe
•0507 - Waste Deck Plate for Hose
•1269 - Waste Deck Plate for Hose
•0524 - Waste Deck Plate for Pipe