Foamy drive oil
 

I am running B-Max drives. I had the drive oil changed out and they used the amber looking Merc brand. Now my drive oil is foaming up in the reservoir. What can be causing this?
Thanks

Personally, I wouldn't use the regular Merc gear oil. Mercury developed the high performance lube because the regular gear lube wasn't good enough and they were eating Bravo drives when they were developed in the late 80's. I think the general rule of thumb is use the high performance lube at minimum on anything over 75 horsepower. And I didn't mistype that, seventy five horsepower.

At minimum switch to the blue stuff or find what other BMax guys are running. Amsoil? or something along those lines I suspect is probably more normal

As of the past couple years Merc Drive lube has been marketed as: "High Performance" is the standard drive lube for Alpha and Bravo 1. "Extreme Performance" Quicksilver is the exact same lube as "Mercury Racing" just different packaging for retail sales. Both recommended for XR and Up, High Hp Applications.

I sent one of my bravo drive for a total inspection, opening the drive, changing whatever was needed.. after all my drives were not checked or open in the last 13 years!

result was: nothing needed to be changed! Been running synthetic 75-90

the only thing they told me was
NEVER USE SYNTHETIC OIL in these drives! Like never never! Not good for the drives, too thin and so on...

not sure why they put the emphasis on that... remember i ran them 13 years without any issue! I dont understand that... so i switched back to merc hi perf 85-90...

i hope they dont blow up !!!

I'm pretty sure Merc High performance lube is synthetic.

^^^^^ Huh?

I would check and see what's supposed to be run in a BMAX....I could be wrong but I thought I remember reading that one of these aftermarket type drives ran motor oil instead of gear lube...can't remember if it was BMAX or something else entirely but that would explain the amber colored oil if that's the case....regardless it clearly doesn't like what's in there so I would either not run it or be super easy on it until you get this resolved. I'm thinking it's probably a cavitation type issue causing the foaming...same as when you run a crankshaft through your pan and the oil is too high and it starts foaming the oil...just a guess but like I said I would figure out what oil is recommended by them and change it immediately if it's different than what's in there.

wrong tread my bad...🤦🏻‍♂️

Funny this topic came up, I had foamy **** in my reservoirs this weekend. I have always run the Merc Racing gear oil and I change it every 40 hours. Its always looked good, my drives look great, and I run my boat hard. I have just changed my gear oil and used the same Merc Racing lube, but I thought it looked a little different. Kinda had me questioning it. I have maybe 8 hours on it right now. I went out for a hard run, full throttle for 20 miles or so. My alarm came on for a drive lube indicator. I checked and it was all foamy in the reservoir. I topped it off a bit and went back to running but its definitely foamy and I've never noticed that before. I cooled it off the rest of the weekend becuase I had my family with me, but it was still foamy when I put it on the lift before I left. I'm gonna switch to something else like Redline.

For B Max drives, I’d use the Bravo Shop Neo gear lube or the Merc Racing/QS Extreme Performance

was going to say the same. Use the neo oil.

also not sure what resevoir style you have but they have one way check valves in the caps. The system should be sealed. If it isn’t or the valve isn’t working it will lead to foamy oil.

Another thing I would do…stick your finger in the oil and get a read on coloring. When I had xr issues back in the day oil was turning black and we couldn’t tell in the bottle without actually dipping something in it.

This helps me and definitely something for me to look at. My caps have never sealed great..like the threads are off. I have replacement reservoirs so I'll do that.

clean like what? Put brake cleaner in tank and let it drain from the drive?

Look at the other post by this,,,,"login", its AI.