[C320-list] Deck filler O-rings

[John Stetson]

I just replaced ours.  After a little trial and error, the correct sizes
are:

   - Water and Diesel - 1-1/2" by 3/32"
   - Waste - 1-3/4" by 1/8"

West Marine did not have the right sizes, but the local hardware store did.


John Stetson
Hull #578


On Tue, Sep 1, 2020 at 5:16 AM Dennis Cookson <dennis at cooksons.net> wrote:

> I need to replace the o-rings in all my deck filler caps, and I can see
> that many owners have done this, but I can’t see any info on the size/spec
> of the replacement ring.  Does anyone know the exact spec, especially for
> the ring fitted to the diesel filler cap on a 1999 vintage 320?   I
> measured the outer diameter of the filler cap threads at about 41.3mm
> (1.625”) so presumably the o-ring inner diameter needs to be a little
> smaller for a snug fit, perhaps 1.6” or even 1.5”?  The cross section
> diameter appears to be 1/8”.
>
> Are the diesel and water filler caps sizes identical?
>
> Dennis Cookson
> #577