Hello,
The Volvo transmission shift solenoids are now a sealed unit, which protects the connection from water and corrosion. As Andrew and others have mentioned, it is very important to keep the packing gland adjusted properly and ensure the aft bilge pump is working and keeping the water below the shaft. We also recommend using a dielectric grease on both the top and inside of the two (yellowish) connectors to avoid water intrusion.
To bypass the solenoids and manually engage the gear:
1) Stop the engine and turn off the engine display
2) Disconnect the wiring connectors on top of each shift solenoid
3) There is a very small (2mm) allen screw in the center of each solenoid that is only accessible with the connector disconnected '
4) The solenoids are labeled "A" and "B". The "A" side controls forward, and "B" is for reverse. Turn the small allen screw clockwise on either solenoid dependent on which direction you need to move
5) Power on the engine display, you will immediately have an engine warning concerning shift solenoids which you will ignore
6) Start the engine, which will go directly into gear (forward or reverse depending on which solenoid was bypassed)
7) Get the boat to the nearest safe location to repair the solenoids
The newest Volvo operator manuals outlines this process which I've copy and pasted below. Please feel free to reach out directly with any questions I can help answer.
Thank you,
Tim
Emergency Shifting If a fault occurs that prevents engaging gears with the control lever (shifting), it is possible to engage them manually.
Manual shifting of gears
1 Stop the engine and turn off the ignition. If the boat is equipped with an ignition switch lock, take the key out of the switch lock.
2 Look for the “A“ and “B“ markings on the cable for the reversing gear shift solenoid valves. Use a screwdriver to pry off the black protective shroud enclosing the electrical connections to the solenoid valve. Then disconnect the white connector from the solenoid valves (2).
3 Normally the “A“ side is set for forward motion in a single installation, and in a dual installation it is set for forward motion from the starboard engine. Insert a 2 mm Allen key into the "A" connection (3), then tighten the solenoid valve emergency screw at least 5 turns clockwise.
4 Now the gear operation has been activated for forward movement. Switch on the ignition. Fault codes can now come from the EVC system, which is normal as the shift solenoid valves are disconnected. NOTICE! Forward gear is now permanently activated and cannot be disengaged by the control lever. Adjust your speed accordingly!