Leaking still agitator shaft seal

[Distiller Mike]

Hi all,

I am running a Kothe Standard 400L still. The agitator shaft seal, just before the gear reducer is leaking distillate out of the "weep holes" just after the oil seal located in the stainless collar. I have replaced the seal several times as well as well as the motor and shaft. Leak remains. Has anyone else experienced this? Any advice is greatly appreciated. 

Thanks!

[ChrisSD]

Do you have any pics?

[Distiller Mike]

Hi, thanks for responding. Yes I do. And sorry, I have been out for a few days. 

[Silk City Distillers]

Interesting color and location.  You are sure that's not oil from the gear reducer?  Can you confirm you are actively leaking vapor during distillation?  It would be quite obvious.  Given how dark that is, the location of the gear reducer, it's possible that you are leaking oil from the output shaft seal of the reducer.

[whiskeytango]

have you called Kothe?  Seems like they would know what to do.

 

[ChrisSD]

Silk is right, it does look off in color.  If it is in fact the distillate, you can try some petrol-gel. It might be just enough to get a vapor seal.

http://www.petrolgel.com/

[Skaalvenn]

These mixers don't use packed teflon packing for the seal?

[Distiller Mike]

Thanks for all the suggestions. It is not great reducer oil. I have pulled the motor several times. And it is even a new motor. There is a teflon support to support the shaft deflection. What I have found is that the seal installed and being supplied is not ethanol resistant. Oh and how I have tried Kothe over the last year. Last I heard was that "he" was going to talk to the engineers in Germany and then back to no replies. Upon my own research, I am finding that A) the seal obviously needs to be ethanol as well as temperature resistant and B)) be able to support the radial shaft deflection at a roughly 20° offset that the shaft is sitting at. And yes, I can actually see vapor coming from the weep holes and it tastes somewhat like tails. In the stainless collar, there are 8 "weep" holes just before the gear reducer that is designed to vent distillate so that it does not ruin the reducer bearing. Eagleburgman seems to specialize in these seals and agitator specialty seals that can handle a 1.5mm deflection. What ever you do, don't use the seal shown below. 

[Dehner Distillery]

Teflon coated packing with a tensioner. would fix that.

Or a different mixer.

[Stumpy's]

Our Corson still had similar issues. Bottom seal on the gearbox was junk and all the oil ran out. We applied a "farm fix" to it and it has worked like a charm so far. I pulled out one of the oil sight plugs and put a grease zerk in its place. We packed the gearbox full of food grade grease and it has been working like a charm. Even if the seal junks itself again, being the correct material the "leak" issue will take a lot longer to show itself. We've done this on a bunch of gb's on the farm...the ones on the mower have been running for years like this. Just hit them with a few pumps every now and then. It also makes me feel MUCH better having something food grade in that box instead of gear oil in case of another failure...nothing nasty can make its way into the pot.

[Distiller Mike]

Fixed. Boiled down to shaft deflection. If anyone has the same issue, I'm here to help. It was never gear box oil/grease as others implied. I found (after a year and a half) that it is rather an easy fix. But it was not easy to come by. I will not disparage more than saying this manufacturer had a lack of design. I had my own parts machined. Don't follow the 9, 6 and 4 thousand dollar fixes. 

[Southernhighlander]

I've seen that black stuff before.  It was lipids from a corn mash.