Troubleshooting Leaking Seals

As a mechanical engineering services company and a distributor of Wartsila Seals and Bearings, one of the most common service calls we get is a leaking seal. Fortunately, troubleshooting and correcting leaking seals can be simple. There are three types of shaft seals: 1) packing glands/stuffing boxes, 2) lip seals, and 3) mechanical seals.

Packing glands or stuffing boxes have flax packing wrapped around the shaft to prevent water flow. It’s common for these seals to drip, but the packing nut should be tightened if the drip becomes more frequent. Threads should be kept lubricated with Teflon or Boeshield T-9. If tightening doesn’t stop the constant leaking, new seals are needed. 

Lip seals are self-aligning and do not drip, making them easy to maintain. Wear on lip seals is caused by damage or corrosion to the shaft, which will cause leaks. Machinery operators can simply cut off the damaged lip seal and slide the spare into place to repair lip seals.

Wartsila seals make up two mechanical seals. They have carbon faces/seats, and one of them is mounted to the stern tube and another on the actual shaft. If there isn’t proper water flow, these seals will experience leaks and burnout.

Waterflow is crucial when it comes to troubleshooting and the overall maintenance of seals. If water injection lines are present, they should be monitored regularly. The leading cause of seal failure is a lack of cooling and water flow. Other causes include wearing, tears or fractures. Although these causes are less common, they are still a good indicator of a bent shaft of a significant misalignment. If damage is apparent, it’s best to have a reputable mechanical company come out and investigate. 

AME recently troubleshot and rebuilt a Wartsila Shaft Seal for a 144' Heesen. Check out the photos on the left!

AME is an authorized representative for Wartsila Seals and Bearings. With locations in the yachting capital in the world, Fort Lauderdale, FL, along with the capability of traveling worldwide, AME can mobilize quickly to help with a leaking or damaged seal emergency.