Boatnerd Discussion Forum

Good to know. Thanks for sharing.

Know of it happening including on a warship in the 70s. Around the propeller shaft is a "shaft seal." It keeps the lubricating oil and other petroleum from leaking. Not wide on a propeller shaft. But monofilament is thin enough that it works its way in. Being functionally fiberglass, it cuts/shreds the seal and destroys it. Depending on how far it works its way along the propeller shaft, it has disabled vessels by freezing the shaft. Not a frequent occurrence but a known hazard. Not just birds are hurt when fishermen discard it in the water.

I'm confused as to how fishing line could cause a problem that would require partial unloading and repairs on a large laker. Can someone clarify?