Problem solved. But what if you can’t find an exact match in the SAE box, or the original O-ring is a weird color or has flat sides? That’s when you enter the world of SAE vs. metric O-rings ...

That box of assorted rubber O-rings under the workbench in your shop might supply the cure to leaky hydraulic connections, or it might just interrupt the leak for a day or two. Flat-face hydraulic ...