Condensed milk - final drive!! Advice needed.

oddshapedballs

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So, dropped the final drive oil out of my 2011 GSA at the weekend and it was like condensed milk, clearly some water ingress but I checked everywhere and couldn't identify where it was getting in, I then pulled back the front-top of the rear swingarm gaiter and a small trickle of water came out of the bottom-back of the gaiter, on closer inspection the gaiter was split from the harder plastic sealing ring...would this be the cause? how would the water get into the rear hub from there?

Ta.
 
I've had this with mine. I reckon it it gets in through the rubber breather on the top when washing. I put new oil in and went for a run and changed it again when I got back and now try to avoid it with the pressure washer.
 
Is your FD not the one with the breather in it? If so there are tons of threads complaining that the water gets in there. The swingarm isn't sealed and never has been on the Hexhead. Gaiters only stop you sticking your fingers into the joints.
 
Oil seals work very well in one direction, not the other...

Water gets into the area at the input shaft to the final drive and submerges the seal, oil gets hot and tries to escape seal holds positive pressure...

Oil cools and creates a slight negative pressure inside the final drive, if the water is on the outside of the seal guess what it sucks in....

My 2008 GSA did the exact same thing. My bike now has a nice 6mm hole drilled at the bottom of the swing arm casting to prevent it happening. I poke an old cable tie up there once in a while to ensure its clear...

Roger...
 
Had that in mine, just before both seals failed.
After having a good look at a breather, I'm not convinced that water can easily get in there. Although I still wouldn't get to enthusiastic with the power washer.
I think that the FD oil simply absorbs the moisture that's in the air. Think it's called hygroscopic?
I think regular changes are essential and I'm not convinced that it's done on schedule when in for a service. Don't believe mine had ever been changed in the five years before I bought it, despite having all the dealer stamps.
Now it's turned 40k miles, I'm doing my own from now on.
 
Mines done 31000 now and I've changed the oil every 6,000 from 6,000 miles and it only happened once at 24,000 which makes me think it was the pressure washer.
 
Is your FD not the one with the breather in it? If so there are tons of threads complaining that the water gets in there. The swingarm isn't sealed and never has been on the Hexhead. Gaiters only stop you sticking your fingers into the joints.

Yep, breather in my FD.
 
Thanks for the replies chaps, seems more of a common complaint than I'd anticipated, I'm going to change the gaiter, stay away from pressure washing it and change the FD oil a few times over the next couple of months and go from there.
 
It happened to me. I changed the oil, ran the bike for a thousand miles or so and changed the oil again- it came out clean and has done since, at every annual service (that's only about 4000m for me). The FD is quiet and no play in bearings. I think it was a badly fitted gaiter.
 
Mine did it after riding through flood water a few years ago. Submerging the FD in cold water causes it to suck in water past the seals. Changed the oil twice since, both times clear and golden.
 
. Submerging the FD in cold water causes it to suck in water past the seals.

Thats the one... the FD will be hot therefore the air inside has expanded, when you cool it quickly the air inside shrinks and sucks in around the seals or the breather - if you happen to be in water then it sucks in water, i don't know if you'd get the same effect with washing when it's hot, try letting it cool then washing it. The same thing happens with land rover swivel's and the like when you go wading with a hot vehicle, it sucks in water everywhere.
 
The oil in mine at the first change by me stank horribly. Mileage was around 36K. At 50K all bearings were at end of life. Mikeyboy rebuild.
Was the oil in mine ever actually changed during that first 36K miles? Who knows. I've never had mayo oil but never waded it through deep water. I do use the pressure washer.
 
I changed the FD oil for the first time on my old 2005 GS since I bought it a couple of years ago and decided to lube the prop shaft splines at the same time. The final drive oil came out fairly black, but there was a condensed milk like fluid inside the swing arm. Still don't know what it was or how it got there.

Oneplus 2 = my phone
 
I changed the FD oil for the first time on my old 2005 GS since I bought it a couple of years ago and decided to lube the prop shaft splines at the same time. The final drive oil came out fairly black, but there was a condensed milk like fluid inside the swing arm. Still don't know what it was or how it got there.

Oneplus 2 = my phone

Oil in the swing arm = leak from gearbox or final drive bearing seals.

Changing the final drive oil is one thing. But the trunnion bearing is needle rollers. These are under-greased by the factory because people complain. Wiping away a little excess is too technical.

Tipping the drive backwards helps to recirculate the grease. Even better strip clean and regrease the bearings.
 
Oil in the swing arm = leak from gearbox or final drive bearing seals.

Changing the final drive oil is one thing. But the trunnion bearing is needle rollers. These are under-greased by the factory because people complain. Wiping away a little excess is too technical.

Tipping the drive backwards helps to recirculate the grease. Even better strip clean and regrease the bearings.
I'll add that toy to do list. What's the best type of grease to use?

Oneplus 2 = my phone
 
What's the best type of grease to use?

Ideally a Molybdenum Disulfide based grease. This will bond alternate microscopic layers of sulphur and molybdenum to the components, allowing the splines to move against one another under pressure without causing wear or corrosion.
 
Ideally a Molybdenum Disulfide based grease. This will bond alternate microscopic layers of sulphur and molybdenum to the components, allowing the splines to move against one another under pressure without causing wear or corrosion.
Great, thanks. That's what I used on the splines too.

Oneplus 2 = my phone
 


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