Catalina 34

General Activities => Main Message Board => Topic started by: tommyt on May 20, 2014, 11:24:27 AM

Title: Deck fill O-ring
Post by: tommyt on May 20, 2014, 11:24:27 AM


I have searched and not found a likely hit. Looking for the O-Ring for the stainless deck fill for the forward water tank.Actually, on the 2004 cC-34 all the deck fills are the same. Just need the O-Ring , and the only rings I am finding are two thick.

Any suggestions?

Thanks,
Title: Re: Deck fill O-ring
Post by: Stu Jackson on May 20, 2014, 01:09:59 PM
Any good ACE Hardware store should have a large collection of O rings.
Title: Re: Deck fill O-ring
Post by: tommyt on May 22, 2014, 10:09:06 AM
Did not find at an ACE, but found as hardware with a selection of O rings and seals that shocked me. Thanks for the hardware idea Stu.
Title: Re: Deck fill O-ring
Post by: Craig Illman on May 22, 2014, 11:35:07 AM
It's a lot handier to have an ACE (or equivalent) close to the marina, than a West Marine. Walking distance is every better.  :thumb:
Title: Re: Deck fill O-ring
Post by: Ron Hill on May 22, 2014, 07:10:43 PM
Guys : Anytime you need a new "O" ring go to an automotive or a tractor store - beside a hardware store.  A thought
Title: Re: Deck fill O-ring
Post by: Phil Spicer on May 23, 2014, 05:43:26 AM
   NAPA near me will make up O-rings. Walk in with your old one and watch them make your new one. As Ron said, auto stores
are another good place for parts. I have found most of the big auto stores near lake Erie have many marine parts...but not like
Auto Zone.
Title: Re: Deck fill O-ring
Post by: Indian Falls on May 23, 2014, 09:49:10 AM
If you can specify Viton or Silicone you won't have to replace the oring for 10 years.  Buna orings common at hardware stores, Napa, etc... will only last a season or two.  The orings that come with most fill caps are Buna and crack, split in one season in my experience.  You can also buy orings on line at more than 100 outlets... start with a search for "orings.com"
Silicone orings are orange most times, Viton can be black, or brown.  Viton is a trade name like "Xerox". Viton is a fluoro-elastomer synthetic rubber.
Title: Re: Deck fill O-ring
Post by: Breakin Away on August 18, 2018, 07:44:45 PM
Does anyone have a dimensional spec for the deck fill o-rings? A couple of mine are starting to crack, and I'd like to replace all four (2xwater, waste, and diesel). I measured approx. 1-5/8" OD, but was having a hard time measuring thickness. I'm concerned that if I try to remove it to do the measurement, it will break, then I'm SOL until I find the replacement. I'd rather buy first before removing the old ones.
Title: Re: Deck fill O-ring
Post by: KWKloeber on August 19, 2018, 08:52:01 AM
Duct tape over the fill and take the plug to the hardware store/plumbing supply house.
Title: Re: Deck fill O-ring
Post by: Ron Hill on August 25, 2018, 01:35:58 PM
Guys : I always kept the "O" rings from the Old Caps as they usually got chewed up, cracked or UV damaged and needed to be replaced!! 

I'd just remove one of the caps' "O" rings and take it to an automotive supply and get a replacement.  Just tighten down that cap and I'm sure that nothing will get into a tank while you're getting a replacement.

A few thoughts
Title: Re: Deck fill O-ring
Post by: Breakin Away on March 13, 2020, 09:09:48 PM
After searching high and low trying to find the required 0.1" thick O-rings, I finally found the right ones. As others have pointed out, the commodity O-rings found at hardware stores are usually made of nitrile rubber (Buna-N and similar), and don't last. I found Viton ones with the right dimensions and a Durometer hardness of 75. Viton is about 10x-15x more expensive than Buna-N, but it's preventing contamination of your diesel and water, so you want it to last.

For the water and diesel caps, the proper O-ring on my boat is 1-7/16" ID x 1-5/8" OD (3/32" Width). This corresponds to aerospace standard (AS568) size 127.

I had to purchase 10 of these, which is more than I need. I'm willing to sell several for $6 for a set of 3 (2 for water + one for fuel) - contact me through the website if you're interested. However, first verify your dimensions, since you may have different dimensions on your boat.

The holding tank deck cap is different and needs a larger O-ring that is 1-3/4" ID x 2" OD (1/8" thick). This corresponds to aerospace standard (AS568) size 224. I did not replace this one, because my current O-ring looked fine, and rainwater contamination is much less of an issue for the "honey pot".
Title: Re: Deck fill O-ring
Post by: Ron Hill on March 14, 2020, 12:49:51 PM
Guys : Treat the "O" rings with silicon spray or plumbers grease and when you tighten them down "snug" is all that is needed!!

A few thoughts