Water in the final drive?

[rangerguy302]

Ok, I did the 750 final drive swap after discovering the shaft was ate up, no grease for YEARS. I changed the fluid and all then it started spitting oil, knowing it's not over full I drained it and it was brown cream looking crap. I check all fluids regularly and keep seeing that brown cream in there ever time. Any ideas where it can be coming from? I'm not scared of the rain but I can't see water getting in there from that. Thanks for your time and Merry Christmas ⛄

[Radioguylogs]

Condensation?

Zealous washing?

That's really strange.

[bikerphil]

If you rode thru some deep water that was over the top vent, I can see this happening.

[skids]

Ok, I did the 750 final drive swap after discovering the shaft was ate up, no grease for YEARS. I changed the fluid and all then it started spitting oil, knowing it's not over full I drained it and it was brown cream looking crap. I check all fluids regularly and keep seeing that brown cream in there ever time. Any ideas where it can be coming from? I'm not scared of the rain but I can't see water getting in there from that. Thanks for your time and Merry Christmas ⛄

Long ago, I did a final drive swap on a standard. I remember there were two types and I couldn’t tell you which type I had. I sort of remember that there was a seal that needed some RTV, which I did. Could it be that water is entering the swing-arm tube and getting passed the seal (if yours has one)? I am not sure how it could be getting into the swing arm though...

[hamjam]

what Oil are you using in there ?

[motoman]

what Oil are you using in there ?

I would hope he is using 75-140w synthetic(Royal Purple or your choice of synthetic)) in that final drive.

[skids]

Not to derail your post about the final drive, but one of my xs11s had a milky appearance to the oil in the middle drive-almost like clay sludge. Weird stuff. I changed it and it has been normal since.

[rangerguy302]

😂😂 I don't believe I ever got that crazy washing it, no puddles that deep. I'd have bigger issues than the final drive. The oil I have in it currently (changed it today) is 50/50 super tech synthetic gl5 70-w140 and auto zone gl5 85-w95. Not the best I know but it's what I had on hand after I'd already drained it. The final drive swap I did, did require a lot of rtv. As far as the swing arm, it's intact and even put the spring clamp back on it. My middle drive is still nice and dark gold like the day I put it in. I'm wondering if it's just condinsation, it's been cool and muggy in Billings, and unseasonably warm. 50's day time and high 20's at night. I just don't want it to eat the rear end while I'm on it....bad news poppa bear....lol

[skids]

That mix of hypoid is just fine. Was there any appreciable increase in the level of fluid? I can see how moisture gets into the crankcase with combustion gases, but I just don’t see how much can get in the final drive from condensation. BUT, I am not expert in such matters!

[rangerguy302]

Me neither skids, I'm baffled. Sooner or later it'll get cold enough, or ice up, and I'll have to park it. I can do a tear down on the ol thing. Finally got a chance to take motomans advice to day with the kids, couldn't have been a more help being in the way, it was great. Do you think it would hurt anything to remove the vent cover and pipe in a resavore to fill the final drive totally up and push excess gear oil out into the "overflow" tank? Trying to think of a way to keep a better eye on it. That way if it gets that creamy look I can get it out. On a semi related subject, when the drive swap is being done it's the xs850 drive you want not the 750 correct? I used the 750 cause it's what I had.

[DiverRay]

You really do NOT want to mess with the vent! I use a little seafoam or berryman's b12 to wash out the final drive. Let it air out for about 30 minutes then fill to the proper level. I use full synthetic 75/140 in all my vehicles for gear oil. The Concours is ALWAYS ugly when I change out the oil, and that's every 10K.
All I can think of is you washed the bike after a ride, and as the water cooled the final drive it sucked some into the vent. It does not take much water to make the oil look like mud!
I've used both 750 and 850 finals and had no problems.

[hamjam]

Do you think it would hurt anything to remove the vent cover and pipe in a resavore to fill the final drive totally up and push excess gear oil out into the "overflow" tank?.

what are those please i do not think you should mess with the vent at all and never heard of an overflow tank

[rangerguy302]

I wasn't thinking major surgery, just out patient. Remove the cap and put a nipple on it, then a tube into a vented resavore. 1 to keep the rear end plumb full, and 2 to keep an eye on the water in the oil thing. Mabe I'm just being paranoid........ I've kinda gotten to like the old beasty, it seems to not care what's loaded on it. Just goes like crazy. The 9r that I had if I put a passenger in it you could tell, on this torque monster you can't really. Not so much money but alot of time is in this thing, I'm pretty proud of it and want to keep it up long as I can.

[rangerguy302]

O....and I can't spell my way out of a wet paper bag.. lol

[motoman]

I wasn't thinking major surgery, just out patient. Remove the cap and put a nipple on it, then a tube into a vented resavore. 1 to keep the rear end plumb full, and 2 to keep an eye on the water in the oil thing. Mabe I'm just being paranoid........ I've kinda gotten to like the old beasty, it seems to not care what's loaded on it. Just goes like crazy. The 9r that I had if I put a passenger in it you could tell, on this torque monster you can't really. Not so much money but alot of time is in this thing, I'm pretty proud of it and want to keep it up long as I can.

Final drive can NEVER be full. It's rated capacity AND measurement through fill hole is rated in mere ounces. If overfilled, can do internal damage and blow oil out vent on top of final drive.