What's this?

[TortolaTim]

Second question....What is this appendage attached to the side of my fuel filter with the yellow cap? Just got the boat and am combing through the systems getting familiar with everything as it's a bit more complicated than my C22. Thanks again.

[KWKloeber]

Tim

It's Racor restriction indicator -  basically a vacuum gauge on the back side of your primary filter to show when it's time to replace because it's plugged.  It works like a dragging needle vacuum gauge and shows the highest vacuum its seen after being reset. "Theoretically" when the indicator hits red it's time, but I don't know how true that is for our diesels.  A dragging needle gauge is much more useful.

[Breakin Away]

Tim

It's Racor restriction indicator -  basically a vacuum gauge on the back side of your primary filter to show when it's time to replace because it's plugged.  It works like a dragging needle vacuum gauge and shows the highest vacuum its seen after being reset. "Theoretically" when the indicator hits red it's time, but I don't know how true that is for our diesels.  A dragging needle gauge is much more useful.

Due to restricted space, my MkII boat has a similar Racor housing, although my spin-on filter is R15P. I recall someone once posted the source and model of a dragging needle vacuum gauge, but I'm having a hard time finding it now. Could someone please re-post the info, or spoon feed me a link? Also, are there generally any restriction on the orientation of the gauge (vertical/horizontal)? Space is real tight down there.

[KWKloeber]

https://www.amazon.com/Racor-RK19671-Bottom-Mount-Vacuum/dp/B07BDV5LH5

https://www.defender.com/category.jsp?name=vacuum-gauges&path=-1|311|2349076&id=2349087

http://www.designatedengineer.com