How to Replace Hydraulic Fluid on a Outboard Trim/Tilt Pump

by Will Charpentier
Fill your outboard's hydraulic tilt/trim system through the hydraulic reservoir.

Fill your outboard's hydraulic tilt/trim system through the hydraulic reservoir.

When your outboard motor's hydraulic trim and tilt pump is low on fluid, the hydraulic motor will groan and fail, or come close to failing. You'll have to add hydraulic fluid to the system. If you've drained your hydraulic system for maintenance, though, you'll have to replace the hydraulic fluid you've removed with fresh fluid so that your system will work. Making sure that you add enough fluid requires only that you add fluid to the right point.

1.

Open the filler spout on the hydraulic reservoir. Add fluid to the hydraulic reservoir until it's even with the bottom of the fill spout.

2.

Use the trim control to move the motor into the up position, then into the down position several times to burp the hydraulic system.

3.

Raise the motor into the up position. Add fluid to the hydraulic reservoir until it's even with the bottom of the fill spout.

4.

Use the trim control to move the motor into the up position, then into the down position several times to burp the hydraulic system. Repeat until the fluid level remains even with the bottom of the filler on the hydraulic reservoir.

5.

Screw the cap onto the hydraulic reservoir. Lower the engine to the down position with the trim control.

About the Author

Will Charpentier is a writer who specializes in boating and maritime subjects. A retired ship captain, Charpentier holds a doctorate in applied ocean science and engineering. He is also a certified marine technician and the author of a popular text on writing local history.

Photo Credits

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