What kind of sealant for hub motors? Some general information also

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Davidcroatia   100 W

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What kind of sealant for hub motors? Some general information also

Post by Davidcroatia » Sep 19 2020 9:08am

Hello. Considering that hub motors some dont have insulation on hub cork, what kind of sealant do you use? Because there are a few problems, especially those who use it in the rain, but also use it a lot, and need to change hub bearings from time to time. So instead of doing that red stuff where you dip all stator and rotor in it and need to bake it, i was thinking of some high temperature silicon glue. There is a problem also with condensation so what do you think ?

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MadRhino   100 GW

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Re: What kind of sealant for hub motors? Some general information also

Post by MadRhino » Sep 19 2020 9:25am

Hub motors are simple and reliable. Protection measures are required only in extreme abuse. You can ride in the rain for a decade with the cheapest of them. It is the rest of the components that need waterproofing, all connectors especially.
Make it fool-proof, and I will make a better fool.
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Trek Session 10 mod. Variable geometry. 70mph
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DogDipstick   10 kW

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Re: What kind of sealant for hub motors? Some general information also

Post by DogDipstick » Sep 19 2020 12:42pm

I used loctite 504 anaerobic gasket maker.

Best stuff out there dont let a drop of liquid of vapor through. Holds pressure great. Wonderful stuff if you are in need of reliability,. The best in the world use it. I put that sh** on errytang.

https://www.henkel-adhesives.com/us/en/ ... e_504.html

http://media.hiscoinc.com/Volume2/d1100 ... TDS_VD.pdf
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Waddyamean? You cant tell me how many amperes/Ft.^2 of the plate ?!?!? WTF. :x :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

John in CR   100 GW

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Re: What kind of sealant for hub motors? Some general information also

Post by John in CR » Sep 19 2020 1:16pm

You should check out Justin's video about water entry. Basically if you ride in the rain a lot you won't be able to prevent water from getting sucked into the motor, since even if well sealed the negative pressure resulting from cold rain cooling a warm motor will suck water in through the wiring acting like a straw. You've got 2 options:
1. If you can tolerate the occasional drip of oil, put some ATF in the motor and pick up the added benefit of better cooling.
2. Put a drain hole at the perimeter of one of the side covers to easily drain any water as well as allow water vapor to escape.

I totally disagree with completely coating the stator with one of those electric sealants. The most I coat is the end lams (the part facing the magnets) and the circuit board for the halls, which I do only if taking the motor apart for some other reason. I definitely would avoid coating the copper, because it already has a high temp coating, and any more will reduce the rate at which a hubmotor sheds heat. I've had ventilated motors since 2011 and have never had any water or debris related related issues with any of them, and that includes several months some years ago where one of the volcanoes was more active cause magnetic dust to settle everywhere.
Last edited by John in CR on Sep 20 2020 12:14pm, edited 1 time in total.

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DogDipstick   10 kW

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Re: What kind of sealant for hub motors? Some general information also

Post by DogDipstick » Sep 20 2020 11:36am

John in CR wrote:
Sep 19 2020 1:16pm
You should check out Jus... got 2 options:
1. If you can tolerate the occasional drip of oil, put some ATF in the motor and pick up the added benefit of better cooling.
2. Put a drain hole at t....
IDK whay everyone says you will leak if you use ATF. I have, and nada drop. Maybe it is the axle is sealed, I never messed with it.... Or I dont have alot in...( 200-350mL?) but I have not leaked a bit with the stuff I recommended. I could see how people do with normal junk silicone rtv.

Yes, i did seal it twice, cause of mechanic mess up ( thought a replaced sensor was bad so I opened a newly sealed hub) and yes, overnight I did see condensation and vapor that had condensed inside the hub or went i through the wire the bath the night before.... However there was no rust from the coating of ATF. Water eventually does get under the oil though.. I have not opened it since in 1500 mi. I honestly wouldnt be surprised if there was an actual volume of water condensed along with the ATF in there now given the time and many bike washes.
83.1v of Ironhorse XC.. :) :bolt: by Chevy :bolt: :D Broke 10 horsies :twisted: (..about 80% healed..).. :? Waddyamean? You cant tell me how many amperes/Ft.^2 of the plate ?!?!? WTF. :x :| (gottenymoem4115thangs?Yall?) :confused: Fabricator @ BSECo. Inc.

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