8.10.4 Mechanical seal

The mechanical seal has the function of preventing sea water from entering the yacht through the space between the propeller shaft and the hull.
It is made up of two sliding rings kept in contact by combined forces. One ring is defined as rotating and rotates with the shaft; the other stationary is bound to the hull.

The seal between the parts is made by means of o-rings.

Cooling of the seal is ensured by the access of water through the flushing duct.

On your yacht, between the bulkhead and the stationary element, the idrostop system can be installed.
In emergency situations and in case of water infiltration from the bulkhead, the IDROSTOP (if present) allows, once pressure has been applied, through the special pneumatic connection (max 3 bar), the return to port in complete safety, keeping the shaft stationary and at reduced speed.

Make sure before starting the engine:

That the seal is also clean on the outside. If foreign bodies are present, it is advisable to wash thoroughly.
That the flush water valve is open and there are no leaks from the sealing surfaces.
of the sacrificial anode’s state of consumption.
For medium-long periods of yacht downtime, follow the instructions in the supplier’s use and maintenance manual..

CAUTION

Install the seal only when the yacht is outside the water.

CAUTION

Never leave sealing surfaces in contact with substances like oil, lubricants or antifreeze.

MAINTENANCE

At least once a week check for water penetration.
At least once a month carry out the cleaning. Periodically:

Check the status of the seals;
Check the compression of the seal and when necessary carry out the compression;
Check and service the cooling circuit of the seals in order to prevent dirt, seaweeds and foreign bodies from blocking the cooling water flow, thus causing the seals to overheat and, consequently, their irreparable damage.

CAUTION

The ongoing navigation and low speed, both forward and in reverse (as in the case of fisheries), it can cause overheating of the seals and their irreparable damage.

CAUTION

After using the Idrostop system (OPT) you must contact the RIVA service.

AFTER-SALES SERVICE BROCHURE

NOTE

For further information on use and maintenance, please refer to the manufacturer’s manual.