Shepherd Hydraulics & Pneumatics

Before checking anything, isolate the machine and release stored pressure. A pinhole leak on a live system can inject oil through the skin, so trace suspected leaks with a piece of card and keep your hands clear.

Here's a rundown of what you're most likely to come across, what each is for, and how to tell them apart when you're staring at a parts drawer trying to match one.

Hydraulic systems use a liquid, almost always oil, to transmit force. Pneumatic systems use compressed air.