The Lasdrop TriSeal was designed for large vessels with 5 - 12 inch shafts. The unit is bolted to an existing flange on the stern tube. The unit encompasses two lip seals that are split for easy replacement without the need for removing the shaft from the coupling. It also has available an optional inflatable seal enabling service to be done in the water.

• Dual split lip seal design.

• Optional inflatable inner seal designed to ease maintenance it also provides easy replacement of the lip seals without the need for pulling vessel out of the water.

• Utilizes split lip seals for easy replacement, making it unnecessary to remove the shaft from the coupling.

• Available for shafts of 5-12" (127 mm - 300 mm).

• Accommodating any bolt pattern for up to 18" diameter flange.

• Manufactured and engineered in USA.

Installation Tips
• Do not use oil or grease. During operation on a mechanical face seal, water hydroplanes between the seal surfaces for cooling and lubrication. This will distort the hydroplaning and will cause a spray or mist during operation.

• Be cautious not to scratch, chip or the like to the seal surfaces. This will also cause an interruption in the hydroplaning.

• Use liquid hand soap for ease of assembly.

• When any service is performed, it is recommended the vessel be out of the water.

• Do not exceed recommended compression. Orange (current) bellows model ½”, Black bellows ¾” and Generation II ¼”.

• Do not remove shaft from coupling or removal of engine while vessel is in water. This may lead to seal surfaces opening up.

• Do not tighten factory installed hose clamps on friction ring assembly. If needed contact factory.

• Do not remove or tighten hose barb in seals using OIN (Oil Impregnated Nylon, green in color) as a friction ring assembly. Contact factory.

• Periodically insure water injection is present during engine running at all speeds.

• When vessel is out of the water for any period of time, it is recommended seal is washed down with fresh water.

When any unusual conditions occur contact customer support.

















All Lasdrop models are complete kits for quick and easy installation. Models are available to accommodate shaft sizes of 3/4” to 8" to fit stern tube diameters up to 10 1/2”. Metric and custom sizes are available. We also offer a complete line of flange adapters to allow for any stern tube configuration.