Bravo 3 and gear lube

[lakershaker]

Last weekend my gear lube alarm went off due to a very low reservoir, and I had to fill the tank. I had the sterndrive service done this spring, but it seems that each year I run through a whole tank of gear lube while putting about 40 hours on the engine each year. Is this normal? I want to be sure that there isn't a bigger problem that is being masked.

[Dave R]

Seems normal for B3s, mine's done it for 4 seasons, but will pass a pressure test easily and never shows signs of leakage on the outside or on the water surface around the drive. Not sure why it's normal, but I suspect it's because the counter-rotating prop shafts have much more seal area than a single screw design. More seal area, more chance for seepage. My other thought is that the B3 runs hot and the lube evaporates into the bilge compartment. I check mine all the time and carry a quart of Quicksilver gear lube at all times.

[NoBozo]

Outdrives do not USE UP oil. If the system is "tight" the resevoir will remain full almost indefinately. It is however recommended that you change the drive oil every so many hours or once a season. Just like changing the oil in your car. NoBozo

[jrc]

My experience is that the reservoir will sometimes empty after the first couple of rides in the spring. This usually requires refilling the reservoir. My research on other boating forums points to air bubbles during filling.

Every winter I have my outdrives serviced. This means draining the lube. When they replace the lube they are supposed to feed the lube in through the bottom. If done carefully no air bubbles get in the lube. If they do it from the top or do a sloppy job, air pockets can be caught in the lube. This make the lube seem full but it's not. After a little while of running the air come out, the reservoir replaces the missing lube, and the empty reservoir causes an alarm.

After I fill it once in the spring it never needs lube again. If I needed more lube after that I would worry about leaks.

[robmac]

I keep diapers in my bilge so I don't pump and oil leaks into the lake,I find myself adding to the resevoir every season but the diapers come out clean.your guess is as good as mine. that is the trim fluid not the lower end fluid as posted in a previous post

[jrc]

robmac, on my B3 outdrives the alarm was connected to the remote reservoir for the drive lube. This reservoir is mounted on the engine but the fluid was for the outdrive.I think this is what you are calling lower end fluid. The trim unit is a small pump to move the drive up and down, neither of my B3 boats had a fluid level alarm on the trim fluid.

[jeffk]

Sometimes the alarm triggers towards the end of the season (about 30 hours) and I have to top off the reservoir.

[lakershaker]

Thanks for the replies. Doesn't sound like there is anything I need to be too worried about.

[jeffk]

Outdrives do not USE UP oil. If the system is "tight" the resevoir will remain full almost indefinately. It is however recommended that you change the drive oil every so many hours or once a season. Just like changing the oil in your car. NoBozo

While outdrives are not designed to use up oil, all systems will leak it around seals to some degree. Mine used a little even when brand new. I would speculate that the type of usage, lots of stop/starts, hard turns, long runs at full power, etc. would tend to accelerate the leakage. Age obviously makes seals less tight and leakage accelerates. When my lube usage increased I had a lower end service done and it dramatically reduced the lube use. I look at increased lube use as a warning that other parts may need attention as well.

The fact that drive manufacturers place the lube resevoir in plain sight, provide alarms for low conditions, and document the need to check the level each time you use the boat show that they expect such leakage to occur.

I believe that the fill it and forget it philosophy does not apply to most boaters. Maybe you can get away with that for the first couple of years for a new boat (or new car) but you are taking your chances after that.

[NightWing]

Next time the boat is out of the water, check the props carefully for monofilament fishing line. It can get behind the props and cut the seals.

[NoBozo]

I have a 22 year old Alpha I with over 600 hours on it. It does not have a remote resevoir. The only way to check the oil level is to pull the TOP plug out of the drive and ..in my case, I stick a "white" plastic wire tie in the hole to check TWO Things: One: Oil Level. Two: Oil Color. "New" drive oil is a semi clear dark Green in color. Over time and with use, the color will darken.

However, if moisture (water) gets into the drive through poor seals, or for whatever reason, the drive oil will turn "Milky" in color.. like a milkshake. If this happens it's time to change the oil and then, check the oil again after say 15 hours of use. If the "Milky" oil re-appears, it may be time to check for leaky seals.

One thing that can take out (destroy) seals in a hurry is getting a fishing line wrapped around the prop shaft... behind the propeller hub. You usually have to pull the prop to see this.

BTW: 10 years ago my "mechanic" told me I had water in the drive and should have all the seals replaced. He quoted: "Around $500". I Declined the offer and changed the oil myself and therafter have checked the oil level and color a couple of times a season. This "can be done" with the boat in the water on a calm day but it's safer to check it on the trailer.

My drive is still tight and the seals are "Original". NoBozo

[NH Native]

The reservoir itself, which is a thin plastic, may develop leaks on the bottom molding seam where the alarm sensor and the tube enter. Feel around or use a white paper towel to wipe the bottom of the assembly and look for lube. I had to replace mine this spring. The part number is M806193A47 and they cost $69 (ouch).