We often think our hydraulic hose is leaking because it’s defective or there’s a crack in the line. Both situations are possible, but not as frequent as using the wrong hydraulic fitting type or installing them incorrectly. Plus, if there’s a missing or damaged O-ring, or if the fitting is over/under-torqued, the seal will not align properly. If the fitting is not torqued correctly, the threads can be damaged-- which is even worse, as damaged threads will definitely leak. It’s a fact: leaks are a regular problem in hydraulic systems, with hydraulic fittings being a frequent source. Repairing a leaking hydraulic fitting is complicated and usually not worth the trouble or risk of it continuing to leak. It’s typically much easier and even cheaper to replace the fitting.

Do Not Ignore Hydraulic Leaks 

First Confirm the Fitting is the
Source of the Leak 

As with all leaks, drips will occur at the lowest point of gravity.
When a leak starts at the ridge of your roof, it often ends up dripping from a valley down to the middle of your ceiling. Similarly, hydraulic fluid dripping from a fitting could be coming from higher up in the assembly. Before assuming it’s the fitting, check the assembly components and hose above the dripping fitting to identify the actual source of the leak. If you assume it’s the fitting and replace it without checking the rest of the system, it may continue to leak and you’ll end up with more extensive repairs and longer downtime. 

Some Hydraulic Fitting Styles Leak More Than Others 

Depressurize the System Prior to Any Repair 

Be Sure to Take Proper Safety Precautions When working with Hydraulics 

Final Reminders 

Other practical (and somewhat obvious) steps to take when fixing hydraulic fittings are: 

• Do not over-tighten the fitting 
• Replace O-rings on hydraulic fittings 
• Use a torque wrench whenever possible. The proper torque value is very important because it represents how tight the fitting connection should be for a system running at high pressure. 
• Use the Correct hydraulic fitting 

In addition, make sure to use hose clamps to hold the assembly in place where necessary and be sure the hose is long enough to properly route through the assembly. Otherwise, the hose can crimp, causing it to leak or pull fittings out of place.