Author Topic: Leak/service questions  (Read 9254 times)

tronstein

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Leak/service questions
« on: January 30, 2023, 05:09:33 am »
I tend to see a lot of questions online about Rohloff leaks.  A lot of them seem to come down to what's normal vs. abnormal, and that's mainly what I'm wondering about my specific situation.

I'll get quite a bit of oil under the cable box, axle plate, and transfer box.  Sometimes it gets to the point where it drips on the floor or wicks down onto my brake rotor.  I've heard things about oil changes and how 25mL is more than the hub actually needs and sometimes excess will leak out more easily.  But I'm wondering if my scenario/photos raise any red flags.  Should I replace the paper gaskets or seal ring?  Thanks.

PH

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Re: Leak/service questions
« Reply #1 on: January 30, 2023, 08:23:04 am »
That looks quite a lot, but I would say still within the normal expectation.
Mine have occasionally looked that bad, and one of them could do with the seals changed, though I've been saying that for a number of years.
I use the oil change method described as best practice in Thorn's "Living with a Rohloff" booklet.
That is:
Flush
Add 25ml
Mix well
Remove 18ml

That leaves 14ml in the hub, 7 adhering to the parts (There's never less than 7 in there) and 7 moving about which is likely to be lost before the next change.  This method leaves less oil in the hub, but ensures what's in there is cleaner, and a higher ratio of oil to cleaning fluid, compared with any method that includes adding less oil, you've effectively done an extra flush. 

Since I've been doing this, at least five years, the hubs and external mechs always look cleaner, even the one I suspect has poor seals.  Some report that the hub isn't as quiet with less oil in there to dampen the sound, that makes sense, though I haven't noticed it.


Tiberius

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Re: Leak/service questions
« Reply #2 on: January 30, 2023, 09:35:53 am »
tronstein - My disc braked hub looks just like yours, with a similar amount of leakage. My hub is 8 years old and has covered (very) approximately 25,000 miles. The leak seemed to start after the last oil change in April 2022 - I change the oil annually and I've always changed it as per the Thorn video method.

https://youtu.be/fVhmgqICNhU

Over the last year the leakage has become less and less as the amount of oil in the hub has dropped. I have got into the habit of always parking the bike leaning over to the drive side which if nothing else, stops the oil  dripping onto the brake rotor.

I can assure you that changing the paper gaskets will not stop the leaking.

 I was going to get the main seals changed this winter but I decided not to bother. I have read so much on this subject and the general consensus of opinion (from the VERY experienced, long term Rohloff hub users around here) is that the leaking is nothing to worry about. Even Rohloff say that leakage won't damage the hub, that there will ALWAYS be enough in there to lubricate the hub. The slight caveat I would add is that the leakage IS a problem if you've got disc brakes. However, parking the bike up leaning over to the drive side just about eliminates that problem.

For me - Going forward I have decided to adopt the oil changing method described by 'PH' above and I'm then going to stop worrying about it. I'm convinced my hub will be fine.




mickeg

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Re: Leak/service questions
« Reply #3 on: January 30, 2023, 11:31:44 am »
I think mine leaks about the same.

When I change oil, I do the cleaning flush, then add 15ml.  I suspect half of that leaks out within 500km.

Andre Jute

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Re: Leak/service questions
« Reply #4 on: January 30, 2023, 01:52:41 pm »
Think of a small amount of oil leaking out as a dynamic seal. Where oil is leaking out, water isn't leaking in.

tronstein

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Re: Leak/service questions
« Reply #5 on: January 30, 2023, 10:20:18 pm »
Thanks for your opinions and experiences, everyone.  My other concern is that I don't have a ton of miles on it either.  I would like to try my hand at replacing the seal, but I'm having a hard time finding parts and tools.

Tiberius

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Re: Leak/service questions
« Reply #6 on: January 31, 2023, 08:31:39 am »
I would like to try my hand at replacing the seal, but I'm having a hard time finding parts and tools.

Wouldn't we all ??

I looked into this last year and (from memory) it appears the seals, and tools to do the job, are only made available by Rohloff to Rohloff main dealers.

I found a number of articles on-line and a YouTube video on replacing the seals. Apparently the seals and tools used to be freely available. However, athough it APPEARED a simple enough job, apparently enough people made a mess of it for Rohloff to make it a 'Main dealer' only job.

As said, that's all from memory, but that's about the gist of it or it certainly was six months ago.

I would just add that I don't believe that it's beyond the wit of man to come up with some method of getting the seals out/in (assuming some sort of replacement seal could be found) I just decided that the whole thing wasn't worth the effort.
« Last Edit: January 31, 2023, 08:42:32 am by Tiberius »

rafiki

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Re: Leak/service questions
« Reply #7 on: January 31, 2023, 10:51:02 am »
I had Thorn  change the seals on the Sterling about 3 years ago when it was 8 years old and ~ 45,000 km. I made an appointment and they did the job in a morning. No troubles since.
Brian.

geocycle

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Re: Leak/service questions
« Reply #8 on: January 31, 2023, 06:47:35 pm »
I had Thorn  change the seals on the Sterling about 3 years ago when it was 8 years old and ~ 45,000 km. I made an appointment and they did the job in a morning. No troubles since.

I’ve a mind to do that next time I need a wheel build. After the last oil change it lost quite a bit with small pools of oil from both sides. I can’t decide whether this was just a poor oil change technique or if it is indeed leaking a bit. I’m not concerned that there isn’t enough left in the hub.  I might do another change, taking more care, and see if I get a better result.
 

tronstein

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Re: Leak/service questions
« Reply #9 on: February 01, 2023, 06:38:43 am »
Interesting info about the seal and tool availability.  That makes sense though, and explains why others were able to do it themselves in the past but now we can't find parts!

I'd also like to highlight an excerpt from Andy Blance's "Living with a Rohloff", which was new to me until I saw it here on the forum!

"Oil leaks from the EX box are generally due to the lack of grease inside
the EX box - grease is used as the only seal for this part of the hub.
Fortunately the remedy is very simple - apply grease!"
« Last Edit: February 01, 2023, 06:43:05 am by tronstein »

PH

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Re: Leak/service questions
« Reply #10 on: February 01, 2023, 07:31:29 am »
I'd also like to highlight an excerpt from Andy Blance's "Living with a Rohloff", which was new to me until I saw it here on the forum!

"Oil leaks from the EX box are generally due to the lack of grease inside
it's a bit of a rabbit hole!  The usually concise Mr Blance has been anything but with this gem.
The External mech is made up of two parts, the Transfer Box and the Cable Box, to me it isn't clear where it's suggested I apply grease.  At least two posters, no disrespect to them, "Pack the Ex box" with grease, yet when you delve a little deeper they're doing different things! Both to the cable box and by the time any oil has reached there it's already out of the hub...  On a Rohloff youtube vid about converting to an external mech, the only place packed with grease is the space around the cog under the axle plate, maybe this is what's meant? I periodically clean and re-pack this with marine grease.  I've only once opened the transfer box, cleaned and greased it, though it didn't look like it needed it and won't bother again unless there's a problem.
I do have a maintenance routine for the cable box,  but IMO it has nothing to do with oil exiting the hub.

I'm a bit sceptical, I think if the oil can get past the seal, it's on it's way out and there isn't anything you can do about it. Andre's point, I think in jest, about dynamic seals has some truth, a dry seal is rarely effective.

tronstein

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Re: Leak/service questions
« Reply #11 on: February 01, 2023, 07:56:16 am »
I'd also like to highlight an excerpt from Andy Blance's "Living with a Rohloff", which was new to me until I saw it here on the forum!

"Oil leaks from the EX box are generally due to the lack of grease inside
On a Rohloff youtube vid about converting to an external mech, the only place packed with grease is the space around the cog under the axle plate, maybe this is what's meant?

This is the first thing that came to mind when I read that excerpt, though I'm not sure if I interpreted it correctly.

UKTony

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Re: Leak/service questions
« Reply #12 on: February 01, 2023, 03:14:42 pm »
I'd also like to highlight an excerpt from Andy Blance's "Living with a Rohloff", which was new to me until I saw it here on the forum!

"Oil leaks from the EX box are generally due to the lack of grease inside
On a Rohloff youtube vid about converting to an external mech, the only place packed with grease is the space around the cog under the axle plate, maybe this is what's meant?

This is the first thing that came to mind when I read that excerpt, though I'm not sure if I interpreted it correctly.

What the Rohloff Manual actually says is, “The cable box of the external gear mech should be demounted approx. every 500km, cleaned and the cable pulley lightly greased from the hub-facing side.”

Since 2013 when I bought my Nomad Mk 2 I’ve been regularly doing what I’ve always thought this means as per the following pictures. I’m sure I remember seeing pictures somewhere showing the greasing like this of the hub facing side of the pulley but where I don’t know. I have never stripped the mechanism down any further to grease or re-grease  the small gear wheel referred to above when converting an internal to external mech.

If I’ve missed something please let me know!

Where oil changes are concerned, I have always followed the Rohloff instruction leaflet that comes with their fluids only oil change kit.

I don’t do a high mileage, no more than about 2500 miles a year, and not in severe or unusual environments.

I’ve just removed the ex box on my Nomad, cleaned the area and re-greased lightly the hub facing side of the pulley as per the photos below. That’s all I do every few hundred miles to cover this recommended 500km routine maintenance job.



PH

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Re: Leak/service questions
« Reply #13 on: February 01, 2023, 05:16:29 pm »
I'd also like to highlight an excerpt from Andy Blance's "Living with a Rohloff", which was new to me until I saw it here on the forum!

"Oil leaks from the EX box are generally due to the lack of grease inside
On a Rohloff youtube vid about converting to an external mech, the only place packed with grease is the space around the cog under the axle plate, maybe this is what's meant?

This is the first thing that came to mind when I read that excerpt, though I'm not sure if I interpreted it correctly.

What the Rohloff Manual actually says is, “The cable box of the external gear mech should be demounted approx. every 500km, cleaned and the cable pulley lightly greased from the hub-facing side.”
It does say that, I don't think you've missed anything, you're doing exactly as intended.
What it doesn't say is that this would in any way prevent leakage.  I find it impossible to imagine how lightly greasing a part the other end of the transfer box from the seal would do so.  So, when AB says "grease is used as the only seal for this part of the hub" I don't see how it can be the cable box he's referring to.

Danneaux

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Re: Leak/service questions
« Reply #14 on: February 01, 2023, 09:59:47 pm »
Quote
The External mech is made up of two parts, the Transfer Box and the Cable Box, to me it isn't clear where it's suggested I apply grease.  At least two posters, no disrespect to them, "Pack the Ex box" with grease, yet when you delve a little deeper they're doing different things!
I'm one of those <waves!> :) and you're absolutely correct, Paul; the Transfer Box and the Cable Box are indeed two different things.

I have only packed my Cable Box with (Phil Wood Waterproof) grease and some seems to have migrated into the lower part of the Transfer Box around the shaft engaged by the cable pulley in the Cable Box. It sure seems unlikely it could migrate higher into the Transfer box and all the way to where it could seal an outgoing leak from the hub. My intent was to seal dust and moisture out of the Cable Box, not seal the oil in the hub or Transfer Box. I do think packing the Cable Box with grease does help prevent the entry of dust at the Cable Box/Transfer Box interface and prevent corrosion, but I don't see how it could do much more than that.

I'd sure be interested to hear Andy B's further thoughts on that.

That said, so far (knock on wood!) I have had no -- zero -- hub leaks so far and only the lightest of oil misting residue visible on each side. Of course now I've said that, it'll prolly leak like a sieve!

Best Dan.