AS SEEN IN THE MAY/JUNE '07 ISSUE

Save thousands of dollars in preventable repairs.

As avid fishermen and boaters, we often get so caught up in the action that we sometimes neglect one of the most important aspects of what gets us to and from our angling destinations- our outboard engine. Too often, we don’t invest the necessary time to properly care for the needs our vulnerable engine has, especially its lower unit. Whether you are running wide open running & gunning the deep blue sea for dolphin or spending your time flying across shallow backcountry bays to reach your next honey-hole, one thing is for sure; your lower unit is hard at work. And regardless if you are a professional guide or a weekend warrior, you have to maintain and service your lower unit on a regular basis. If you don’t, it will cost you dearly.

Many of us have bought into the idea of regularly changing the oil in our vehicles every 3,000 miles. But how many of us really pay the same level of attention to the needs of our engine’s lower unit. This mechanical portion of our outboard is crucial, and it needs the same care and affection we provide to more obvious areas of our boat and motor.

Your owner’s manual and your trusted marine mechanic will recommend that you should change the oil in your lower unit every 100 hours or six months- whichever comes first. When was the last time you changed your lower unit oil? It takes less than ten minutes to do the job that could potentially save you thousands of dollars in repairs. If your lower unit oil is left unchecked and/or unchanged, needless wear and tear could occur on the engine’s internal components. Having internal gears repaired or replaced, as every marine mechanic will tell you is both time consuming and very costly.

So how do you go about preventing damage from occurring to this vulnerable component of your engine? You make sure you adhere to a regular schedule of maintenance. Follow the guidelines set forth by your owner’s manual, and don’t put the work on the back burner. The longer you put the easy task off, the greater the chance of something going terribly wrong when you least expect it.

You can accomplish this maintenance to your lower unit yourself with just a few basic tools or you can leave the job to a professional; just be sure to have it done regularly.

Required tools and materials:
-Marine gear oil
-Reservoir with pump and adapter to fit your particular gear oil drain plug hole
-Screwdriver
-Clean dry rags
-Oil collection pan

10 easy steps to change lower unit oil - assuming boat is out of the water.

1) Trim motor to its highest position.

2) Locate the gear oil level plug on the upper portion of the lower unit and the gear oil drain plug at the forward, lower end of your lower unit.

3) Place an approved oil collection pan to capture every drop of the oil that you are about to drain from the lower unit.

4) Use the appropriate size and type screwdriver to remove the gear oil drain plug and then inspect the gear oil drain plug for any excess metal shavings; this could be your first sign of unusual wear and tear. Once inspected, clean the plug with a clean, dry rag and place the drain plug where it will not be misplaced.

5) Remove the gear oil level plug to allow the oil to drain completely out of your lower unit. Wipe the level plug with a clean, dry rag and place the level plug where it, too, will not be misplaced.

6) Trim motor to horizontal position to completely drain the oil from the lower unit.

7) Wipe the area around the drain hole clean with dry rag and securely attach the fitting from the end of your pump that contains the new oil to the drain plug hole (use only the recommended gear oil stated in your owner’s manual.)

8) Pump new gear oil into lower unit until it begins to flow out of the gear oil level hole. At this point, quickly replace the gear oil level plug and tighten.

9) Carefully remove the gear oil pump fitting from the drain hole and quickly replace the gear oil drain plug and tighten.

10) Wipe the outside of lower unit with a clean, dry rag to remove any excess oil and be sure to properly dispose of the used gear oil. That’s all there is to it until the next 100 hours or six months.

Taking proper care of your lower unit is not complicated, expensive or time consuming. The most difficult part for many of us is simply remembering when to perform the scheduled maintenance. Take note of your engine-hour meter reading. If you do not have an engine hour meter, be sure to have one installed as it is well worth the minor expense. Mark your calendar, if needed, to remind yourself that it is time to change your lower unit oil. If you do not use your boat on a regular basis, then simply marking your calendar six months from the date last serviced would be the way to go.

I would like to thank Captain Jay Billow of Mobile Marine Mechanic Inc. located in Port Charlotte, Florida, for his technical advice. Captain Jay Billow has been a marine mechanic for over 15 years and may be reached at 941.625.5329 to schedule any service or maintenance that you may require, or to answer any questions you may have.

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